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In my line of work, you end up with lots of leftovers, and lots of leftovers means that I make a lot of hash. I mean, a lot of it. What better way is there to recycle that little hunk of bacon, that half onion, and that just-about-to-get-wrinkled pepper than to chop them up, fry them in a skillet with cubes of potatoes, and serve them with runny eggs on a lazy sunday morning? (Hint: there is no better way.)
Now, you could take the willy-nilly approach—throw everything together in a skillet and hope that they somehow tornado themselves into a functional 747—but you're much better off applying just a bit of care, knowledge, and gentle guidance to the situation to help guarantee a safe and sound arrival at a crisper, tastier, and altogether better end-destination.
There are always options with hash (usually defined by what's sitting around in the fridge), but the basic steps are always the same. Let's take a closer look.
Step #1: Choose Your Potatoes Wisely
The type of potato you use can have a great impact on the final result. Waxy red or new potatoes turn nice and creamy when cooked, but are terrible at developing crisp crusts. Yukon golds will develop a decent crust and end up with a buttery interior. My personal favorite is regular old russets, which develop the crispest, craggiest crusts that stay crunchy even when dragged through golden liquid egg yolk multiple times.
The lesson? Stick with either russet or Yukon gold.
Step #2: Par-Cook Your Potatoes With Vinegar for Maximum Crispness
Back in my early hash-slinging days, I'd throw raw cubed potatoes into a skillet with oil and let them fry until golden brown. They sure looked like they'd be crisp, but they'd rapidly soften, ending up with a papery, leathery crust.
As anyone who's ever made great french fries knows, you have to double cook them to get them extra-crisp. By par-cooking chunks of potatoes, you help create a thick layer of gelatinized starch around their exterior that, upon frying, subsequently dehydrates and browns. It's this dehydrated layer of gelatinized starch that gives potatoes a lasting crispness (see this article on ultra-crispy roasted potatoes for some more tips).
The issue is that by par-boiling potatoes, you also end up softening them to the point that they fall apart when you try to fry them. There are a couple of solutions to this problem. The first is to par-cook them in the microwave, like I do with this crispy kale, Brussels sprouts, and potato hash. The microwave will par-cook the potatoes without jostling them, which helps keeps the chunks whole.
Another solution is to add some vinegar to the cooking water, about a tablespoon per quart. This vinegar slows the breakdown of pectin, the inter-cellular glue that holds potatoes together. With vinegary water, you can boil potatoes and gelatinize starch without letting them turn soft, making them easy to fry afterwards. Make sure your cooking water is well-salted, too.
Step #3: Add a Meat, Preferably Cured, and GET IT CRISP
Ok, so not all hashes need meat, and to be 100% honest, most of the ones I make at home don't have it, simply because I don't generally have cured meat hanging around. But I'd also be lying if I told you that crispy chunks of cured pork fat aren't extremely delicious.
If I have it, I'll fry up cured pork (or cured beef like corned beef, or cured duck like confit), let it slowly render out its fat (we'll use that fat to fry the potatoes), and cook until very crisp.
Step #4: Fry the Potatoes in Rendered Fat and Add More Fat Than You Think You Need
Once the meat is crisped, you might be tempted to just throw the potatoes in there. Instead, let me recommend a different tack: take the meat out and set it aside before adding the potatoes. You've already got that meat perfectly cooked. Leave it in while the potatoes cook and you'll only end up overcooking it.
Those par-cooked potatoes need a good amount of fat for two reasons. First, without enough fat, they don't make good contact with the bottom of the skillet, and without good contact, they can't fry evenly.
Second, and perhaps more importantly, fat tastes good. The potatoes absorb it, making each bite more succulent and delicious.
Perhaps the biggest mistake I see with hash, whether at home or in restaurants, is not cooking the potatoes long enough. There's no two ways about it: frying potatoes in a skillet until crisp is a long process. Even with relatively high heat, it can take 20 minutes or more. Don't rush it; you want every single surface crisped.
Step #5: Add Seasoning to Potatoes
Once the potatoes are nearly cooked, it's a good idea to start thinking about flavoring them. If simple and straightforward is your goal, then just a bit of salt and pepper will do. In this case, I'm adding a touch of cumin and paprika, flavors that go well with the chorizo, poblano peppers, and cilantro I'm adding to them. Adding the spices directly to the skillet with the potatoes as they fry gives them a chance to toast and develop flavor.
Step #6: Cook Potatoes, Meat, and Vegetables in Batches to Optimize
As with the chorizo, now is the time to remove those potatoes from the skillet (you can drop them into the same bowl as the chorizo to minimize cleanup) to make space for the remaining vegetables. I like to treat my vegetables like I do in a good Chinese stir-fry: sear hard and fast so that you get some nice browning while still allowing them to retain some fresh crunch. In this case, I'm using big chunks of scallion whites along with cubed poblano peppers.
Step #7: Combine Ingredients Before Finishing
Once the vegetables are cooked, I add them to the bowl with the meat and potatoes. Each element here has been perfectly cooked before combining, which means that the whole shebang is going to be all the tastier. You can serve the hash exactly as-is, but what is hash without eggs? You may as well ask me to watch the Holograms without Jem or the Jetsons without George.
Step #8: Drain Eggs in a Strainer for Better Shape
There are a few ways to incorporate your eggs into hash—poached, fried, or simply baked on top—but no matter your method, if you want them to be the prettiest, you should strain your eggs. Straining is a method I first started using for making perfect poached eggs, but it's equally effective for keeping fried eggs nice and tight or baked eggs from running through all the cracks in your hash.
To do it, just break an egg into a bowl and tip them into a fine mesh strainer. Swirl gently, and the excess whites will drip out, leaving you with only the tight yolk and tight white.
Step #9: Baked, Fried, or Poached? Make Your Choice
Now you've got a big decision to make: how do you want to cook your eggs? Fried eggs are probably the fastest. Once your hash is assembled, just fry the eggs in a separate skillet, throw them on top, and you're ready to eat. Poached eggs are the prettiest, but require a bit of finesse (of course, you can always poach your eggs the day before, store them in water in the fridge, then gently reheat them in warm water before serving the next morning).
For my money, baking them is the best way to go for hash. To do it, return your hash to the skillet and make a few wells in your potatoes for the eggs to sit in, then break the eggs into them and throw the whole thing into a hot oven until the eggs are barely set.
Step #10: A Little More Oil Keeps the Eggs From Drying Out
I always drizzle my eggs with just at touch of olive oil, which prevents their top surfaces from developing an unappetizing, plasticky skin.
Step #11: Top it Off Post-Bake!
The last step to truly great hash is to top it off with some fresh ingredients. Herbs, sliced onions or scallions, or a bright vinegary salsa or hot sauce is good. Avocado makes it even better. I can think of precious few situations that wouldn't be better if an avocado were added to the mix. Can you?
With those basic building blocks, you've got a formula to build up any sort of hash that you'd like, simply by mixing around the flavors and ingredients, which means that whether you're heading to the supermarket with some ideas in mind, or just working out of a half-empty fridge and your basic pantry, you know you're going to end up with some pretty delicious results.
Normally I'd try to wrap this up with some sort of clever last sentence or two that calls back the opening and ties the whole article together like a good rug, but in this case, I've just made myself too darn hungry to concentrate. I'll be right back, gotta throw some potatoes on the stove.
About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.