The Food Lab: The Science of the Best Yorkshire Puddings

The Food Lab

Unraveling the mysteries of home cooking through science.

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Extra-tall and extra-crisp Yorkshire puddings. [Photographs: J. Kenji Lopez-Alt]

Back when I was earning my wage as a cook at a co-ed fraternity house, I received a special dinner request from a few exchange students from Cambridge University: toad-in-the-hole, the classic British dish of sausages baked into a large Yorkshire pudding. Only problem? I had no idea what a Yorkshire pudding was. It was described to me as "sort of like a batter and you pour it into a pan and you bake it." Rather than, say, doing some actual research, I decided to wing it.

Pudding, I thought to myself. That ought to be rich and moist and sort of spoonable like a custard, right?

I ended up with essentially that: sausages baked into a vast pool of eggy custard, their tops just poking through the surface, like a construction worker who's fallen into a vat of half-set concrete. (And the dish was just as heavy as it looked.)

The one good thing about cooking for a fraternity house is that college students will eat anything. Still, at the behest of the British students, I dove a little deeper and discovered that Yorkshire pudding is really nothing more than the British equivalent of the popovers that my mother loves. Sure, our popovers are baked in specialized tins and typically served sweet while Yorkshire puddings are served with beef drippings and gravy, but conceptually they're pretty much exactly the same.

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Yorkshire puddings are traditionally cooked in large pans, though most modern recipes call for muffin tins or popover pans.

This was well over a decade ago and I've spent several months in northern England as well as many hours in the kitchen baking pudding after pudding since then.

Printed recipes for Yorkshire pudding go back as far as the mid-18th century, and the dish likely existed long before that. It's simple—almost primal—in its ingredients and process: Mix together milk, eggs, and flour with a pinch of salt to form a batter ("as for pancakes," according to the 1937 cookbook The Whole Duty of a Woman), then pour the batter in a pan that has been greased with the drippings from a roast. Originally that roast was mutton, these days it's more likely beef.

A Yorkshire pudding works on the same principle as a French pâte a choux, the thin pastry used to make cream puffs, Parisian-style gnocchi, and gougères. Those recipes all start with a high-moisture dough and rely on the power of steam to puff and rise into their light, crisp final forms. Yorkshire puddings and popovers take the same concept to the extreme, using a batter that is so moist that it pours out like cream and puffs up to at least quadruple its volume.

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A hollow core is the hallmark of a good Yorkshire pudding.

As with all simple recipes, Yorkshire pudding technique is steeped in rules designed to make you believe that they're a tricky, fickle food and that following the wrong recipe or wrong technique will lead to disastrous results.

After dozens of tests and hundreds of puddings, I have some good news for you: It's nearly impossible to mess up a Yorkshire pudding (despite the fact that I managed to back in my fraternity chef days). You can play with the ratio of ingredients every which way and still end up with a batter that rises tall. You can bake it in any type of pan you'd like. You can rest the batter or bake it fresh. You can chill it or leave it out at room temperature. Heck, you can even break the cardinal rule of Yorkshire puddings and pour the batter directly into a cold tin. Break every one of these rules and your puddings will still puff and turn out light and crisp.

But of course, some puddings are lighter and crisper than others. I considered it my duty to investigate each and every rule and theory in the lore of Yorkshire pudding to figure out which ones rise to the top and which are simply puff pieces.

Testing Yorkshire Pudding Theories

Before we dive in, a quick shout out to Felicity Cloake's fantastic article on Yorkshire puddings, where, in the true intrepid spirit of an adventurous scientist, she tested a half dozen different recipes before landing on her own version. Her columns are always enlightening and this article hopes to pick up where hers left off.

Yorkshire Pudding Theory #1: Cold Batter = Better Puds

I've heard this one over and over. Make sure that your batter is chilled in the fridge and that your pan with drippings is ripping hot from the oven. But there is debate. The Royal Society of Chemistry rather imperiously advises against it, claiming that to place pudding batter in the refrigerator is a "foolish act." (They, rather unscientifically for an organization of scientists, deign not to explain why.) However, most recipes, like James Martin's, tell you to chill your batter before baking.

This was a very easy one to test. I divided batches of batter in half, storing half in the refrigerator for an hour and the other half at room temperature. I also repeated the experiment with batter I'd refrigerated in its entirety for an hour, then divided, leaving half of it on the counter to come to room temperature before baking. I baked all the puddings in the same tin (repeating the test multiple times, of course), and compared heights and textures.

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The difference wasn't as drastic as some other tests, but the fact is that the warmer your batter is to start, the better your puddings will rise. However, there is another thing to consider: Colder batter stayed pooled in the center as the edges rose from the heat of the pan, weighing down the center and creating a more distinct cup shape to the finished puddings.

Verdict: Depends on what you want. Warmer batter will create taller, crisper puddings with a more hollow core (I kind of like them this way), but colder batter will create denser puddings with a more distinct cup. If you are the type who likes to make a separate onion gravy to pour inside the puddings as a first course, colder batter might be for you.

Yorkshire Pudding Theory #2: You Must Start With a Hot Pan

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Sizzling fat = taller puddings. Or does it?

The idea of starting in a screaming hot pan makes sense for a couple of reasons. First, there's the idea of oven spring. A hot pan will get more energy into the batter right from the start, causing it to puff and rise while it's still relaxed and stretchable. Second is that with a hot pan, your batter is less likely to stick (think: pouring scrambled eggs into a cold pan vs. a hot pan), which means less resistance to rising.

There's no divide on this debate: everybody says you must start with a hot pan in order to get the tallest rise, some going so far as to tell you to preheat your beef drippings for a full half hour before adding your batter.* Still, for the sake of thoroughness, I better test it, I thought. I poured cold batter into a cold, greased tin, then placed it in the oven. At first it looked like not much was happening. But after a few minutes, the puddings started rising. And rising.

*This, for the record, makes no difference at all if you're using a tin. It is as hot after five minutes as it will ever be.

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By the end of their 20-minute cook time, they were nearly (but not quite) as tall as any other pudding I'd baked thus far. Granted, they had slightly different and irregular shapes with less cupping. A couple of them stuck to the bottoms of their tins. Still, the results were far from the disaster I was expecting. When I repeated the experiment in a cast iron skillet, the differences were far more pronounced with the pre-heated pan producing a much taller pudding, and this gave me a clue as to the origins of this particular theory.

With the traditional baked-in-a-heavy-pan pudding, preheating is necessary simply because a cold pan will suck up so much energy from the oven before the batter can really begin to bake. In order to get the batter to heat quickly, your pan must be hot to start. With a modern popover/pudding tin, however, this is not the case. The thin metal is so light that it barely takes any energy at all to heat up. After a few brief moments in the oven, you're essentially in the same initial state as you'd have been if the pan had been fully preheated to begin with.

Verdict: True (sort of). Your puddings will come out slightly higher and better-shaped with a hot tin, but it's not the end of the world if you forget to preheat it. (Just don't try it in a full-sized skillet.)

Yorkshire Pudding Theory #3: Rest the Batter at Least 30 Minutes

Delia, the arch-queen of modern British cookery, declares in her recipe: "There is no need to leave the batter to stand, so make it whenever it's convenient." Jamie Oliver agrees. His recipe has no rest at all (in fact, he doesn't even start making the batter until the tin is preheating in the oven). But Marco Pierre White, a Yorkshireman (as if that really matters), advises letting your batter rest for at least an hour.

When authorities disagree, it's time to appeal to science. I made a half dozen batches of pudding batter, the first a full six hours before the last, then baked them all side by side in the same oven. Amazingly, there was a direct correlation between how long the batter had rested and how tall the puddings rose. You could tell exactly how old a batter was simply by holding a ruler up next to the baked pudding!

Just to be sure of my results, I repeated the test, this time taking it up to a full day of resting before baking. Here are the results:

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Resting the batter is the single most important factor in Yorkshire puddings.

Let me show that to you again, outside of the tin:

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I'm going to say this: Resting your batter is the single most important step you can take to improving Yorkshire pudding and popovers. Not only do they come out taller, they also come out much tastier, with a more complex, toasty flavor. Non-rested-batter puddings taste positively flat (literally and figuratively) next to rested-batter puddings.

In my exploration of chocolate chip cookies a few years ago, I found a similar advantage to resting cookie dough. According to Harold McGee's Keys to Good Cooking, it comes down to the breakdown of proteins and starches over the course of the overnight rest. Here's an excerpt of my explanation in cookies, which applies to puddings as well:

It helps to think of proteins and starches as large LEGO structures. During the process of browning, those large structure are broken down into smaller parts and individual pieces and subsequently rearranged. Sort of like destroying that LEGO castle so you can build a dozen spaceships. Now, both of these phases—the breaking down and the reconstruction—take time.

By resting the dough, you give the deconstruction phase a head start. It's as if you left your LEGO castle sitting out over night and your annoying little sister came by and smashed it all, King of Tokyo-style. With the pieces separated, building your spaceships is much faster.

It's really the same thing, except instead of LEGOs, you've got proteins and flour. Instead of an annoying sister, you've got enzymes. And instead of awesome spaceships, you get awesome cookies. How awesome? We're talking, oh, a million puppies on the moon wearing superhero underpants under their little doggie spacesuits levels of awesome.

Resting makes a big difference in the interior texture as well. With little gluten development, the interior of a Yorkshire pudding baked right after forming the batter is almost cake-like, with small bubbles and not much stretchiness. A pudding baked after an overnight rest has a stretchy texture with large bubbles inside. In most cases, you'll end up with the ideal case: a Yorkshire pudding that is essentially one large bubble in the center. Perfect for holding gravy and drippings.

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The stretchier interior also accentuates that wonderful contrast with the crisp outer shell.

Verdict: True. In fact, I'd go so far as to say that resting at least overnight is essential if you are really after the best.

Yorkshire Pudding Theory #4: More Egg Yolks Make For Richer Puds

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Another easy one to test. I made a few batches of Yorkshire puddings, keeping the total ratio of liquid to flour identical (in this case, both eggs and milk count as liquid), altering the ratio of yolks to egg whites. The more yolks you add to your puddings, the more rich, tender, and custardy they become. The more whites you add, the taller and crisper they puff.

Thankfully, I found that whole eggs gave the most desirable results. Still plenty tall, but not so lean that they become dry.

Verdict: True, but we don't necessarily want richer puddings.

If lowering the amount of fat in a batter makes the puddings crisper and lighter, then the fat content the milk adds to the mix must also have an effect on the end results, right? That brings us to our next test.

Yorkshire Pudding Theory #5: Add Water for Crisper Puddings

Again, this was a simple matter of adding water while keeping the ratio of liquid to flour the same. As expected, puddings with more water in them rise up puffier and crisper. Unlike with excess egg yolks, however, the puddings stay tender enough that the tradeoff is worth it. In my recipe, I ended up using milk and water at a 7:1 ratio (that is, for every 175 grams of milk, I use an additional 25 grams of water). Even easier is if you have skim or low-fat milk—they work just fine on their own, no need to cut them with water.

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I wondered if using soda water might help create an even lighter, crisper pudding. It works wonders in thin batters like tempura—the extra bubbles give it a much lighter texture. With a Yorkshire pudding, the results are not so hot. The fact that the batter is heavily beaten and rested eliminates all the bubbles the soda brings to the party. The batter rises just about the same amount as with regular water. What's worse, soda water is slightly acidic, and the Maillard browning reactions are inhibited in acidic environments, which means that puddings made with soda water come out less brown and less flavorful.

Similarly, adding vodka to the batter (another trick that works well in batters or pastry crust to get lighter, crisper end results) was a bust. It inhibits gluten formation too much, and without gluten, your puddings don't have the necessary structure to puff properly.

Verdict: True. But stick with plain water, leave out the bubbles and booze.

Yorkshire Pudding Theory #6: Beef Drippings Make the Best Yorkshire Puddings

Beef fat has more flavor than a neutral vegetable oil, but the choice of fat in your Yorkshire pudding can affect more than just flavor. It also has an effect on texture. Just like with deep frying, the more highly saturated your fat is (that is, the more solid it is at room temperature), the crisper your puddings come out. Puddings baked with vegetable oil will be limper than those baked with shortening, which will be limper than those baked with beef fat.

Craving puddings without the roast? Clarified butter is an excellent choice.

Another note about fat: As the batter rises, the fat tends to pool in the center. If you use plenty of fat, that pooled fat will weigh down the center of the puddings, creating a deeper cup shape. So for the deepest cupping, use plenty of fat, colder batter, and a slightly higher ratio of flour to liquid in your batter.

Verdict: True.

Yorkshire Pudding Theory #7: Don't Open the Oven While Baking

If there's one bit of advice you hear more frequently than any other, it's this: Do not, under any circumstances, open the oven door while your Yorkshire puddings are baking. Everyone from Gordon Ramsay to Felicity Cloake advises against it. Your puddings will fall, they say. They will refuse to puff, they say. They will spontaneously combust and burn down your house with your goldfish and sense of self-worth trapped inside, they say. They will raid your fridge, finish the milk, and put the empty carton back, they say.*

* They only actually say two out of four of these things.

Fortunately, none of it is true. I baked batches of puddings side by side in two identical ovens. One I monitored carefully through the glass door in the soft orange glow of the oven light. The other I opened up every few minutes to peek along at its progress. (I have two ovens and only one working oven light, so this actually worked out quite well for me.) With the latter, I even took the risk of rotating the tray a few times during baking.

Both batches rose just fine and equally tall.

Verdict: Totally, absolutely false.

Further Testing

Just because I tried to answer all of the most frequently asked questions doesn't mean I was done with things here. I had a few more tests to run through before finalizing my recipe.

Oven Temperature

Hot enough to cause intense rising, not so hot that the exterior burns too fast is the way to go. 450°F (230°C) is ideal. No convection. Some folks recommend turning the oven down towards the end of cooking to allow you to leave the puddings in the oven longer, thereby setting their exteriors more firmly so that they don't deflate as much once you pull them out. I recommend that those folks just learn how to eat their puddings in a more timely manner.

Pan Size

A good Yorkshire pudding batter will work in any size pan. I did most of my testing in large 6-well popover tins, but the batter works equally well in muffin tins, mini muffin tins, and in a preheated cast iron skillet or casserole dish (these large-format methods being the most traditional). It's all just a matter of how you want to present them.

Flour-to-Liquid Ratio

There is a vast range of liquid-to-flour ratios in Yorkshire pudding batter recipes online. Cloake's, for instance, calls for a hydration level of only 140% (that is, for 100g of flour, there are 140g of liquid). The BBC recipe more than doubles that ratio with a hydration level of 285%!

I found 140% to be far too low, with 200% hydration the bare minimum for a thin, pourable batter that rises dramatically.

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More water = higher rise and less cupping.

The higher the ratio of liquid, the more dramatically your puddings will rise, but the less of that contrast between crisp shell and stretchy interior you get. At 300 to 350% hydration you're bordering on a pudding-shaped cracker. With lower hydration levels, you also get deeper cupping. My final recipe calls for 75g of flour for every 200g of liquid for a hydration level of 266%.

Serving Yorkshire Puddings

I have a few bits of advice here, the most important being this: Make sure your guests are seated and ready a few minutes before your puddings come out of the oven. Yorkshire puddings are light, they are delicate, and they lose heat fast. Like time and tide, a Yorkshire pudding waits for no one, so you better be ready when it is.

My mother loves Yorkshire puddings but never gets them enough. The few times we've served them at family dinners, it's been alongside the roast, which lets you mop up the drippings. I've come to prefer serving them the more traditional way: as a course on their own before the meat lands on the table. Serve them hot and filled with pan drippings and gravy. It creates a nice bed in your stomach for your meat and vegetables to settle into later on (and of course, filling up on puddings means more reasonable meat portions later on. The holidays are all about reasonable dining, right?).

Having spent a few months living in the north of England, I have some fond memories of overcooked (but very crispy) beef roasts moistened with plenty of Bisto gravy. No, it's not natural tasting, but yes, it's salty and savory. Typically I eschew store-bought beef stock* for its distinctly fake flavor, but there is something nostalgic about it for me here, where a little store-bought stock flavored with sautéed onions and thickened with cornstarch is an almost perfect match for Yorkshire puddings. Real gravy is great, but don't be ashamed to go with whatever calls to you at the moment.

* Even in meaty recipes, I'll use store-bought chicken stock in place of beef stock, as packaged chicken stock typically has a much higher ratio of actual chicken, while beef stock is not much more than brown water flavored with yeast extracts.

Recently I tried something that might have forever changed my life for the better: thickened French onion soup. I had a few quarts of our recipe kicking around in the fridge (I'm working on a pressure cooker version of that dish). On a whim I decided to reduce it to about half its original volume, jazz it up with a little splash of soy sauce, then thicken it all to a glossy, gravy-like consistency with a cornstarch slurry.

Oh my, was it tasty. For that batch I went with a low hydration batter and a large muffin tin to maximize cupping, turning each pudding into a little tureen for the thickened French onion soup, simultaneously combining three cultures (and probably offending all of them in the process) into one delicious hodgepodge.

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It doesn't matter. I'll take a Yorkshire pudding any time, anywhere, breakfast, lunch or dinner. In fact, I just remembered that I have a cup of batter leftover in the fridge from last night's onion-soup extravaganza. Cuppy Yorkshire puddings with a poached egg and some Hollandaise sounds like a pretty serious end-of-December breakfast to me. All it needs is one of those cutesy British food names and we'll have a new classic on our hands. Muckery cluck or peg-in-pud will do.