Lamb burgers are like the Super Mario Bros. 2 of the burger world. They're kind of strange and funky and it's not entirely clear how they fit into the canon of their brethren, but they're awesome in their own way, and a great change from the norm. I wouldn't eat a lamb burger every day, but when I do, I want it to be the best damned lamb burger it can be.
All too often, lamb burgers fall victim to the same fate that tend to befall turkey burgers: they come so jam-packed with herbs, spices, aromatics, and condiments that they cease to be burgers and end up as lamb meatloaf sandwiches. The very best examples of the form (say, the awesome ones from Balaboosta, The Breslin, or Prune in New York) are first and foremost about the lamb. Funky, minerally, sweet, and dripping with juice, lamb is flavorful enough on its own that you don't need to add anything to it to have a great burger experience.
Still, after grinding and grilling my way through nearly 32 pounds of the stuff, there's a thing or two I learned about the process.
Where's That Lamb From
"Pardon me, good sir, would you perchance divulge the provenance of these fine ovine comestibles?" should be the first question you ask your butcher. Most of the lamb sold in the U.S. comes from three locations: Australia, New Zealand, and the U.S.A. Australian and New Zealand lamb tends to be smaller, leaner, and more mildly flavored, making it a good choice for folks who find lamb to be generally too gamey or barnyard-y tasting.
Personally, when I eat a lamb burger (or a nice rack), I want the full-on, musky, grassy flavor assault you get from larger, fattier American lambs. If you want to be sure he's not—ahem—pulling the wool over your eyes, you can generally (but not always) tell by the size of the racks or legs he's selling. NZ/AUS racks will have an eye of meat about as big as a 50¢ piece, while an American rack will be more like the size of, say, half an iPhone. NZ/AUS legs will be small, like the rear leg of a medium-sized dog, while an American lamb leg will be larger, about the size of Arnold Schwarzenegger's shoulder and bicep, if you know what I mean.
Pre-Ground Lamb ($5 - $8/pound)
Location: Varies. Typically trimmings from shoulder and breast.
Fat Content: Varies depending on where the meat is taken from. Because of the way lamb is butchered and sold in this country, there tends to be a higher ratio of fat-to-meat in a typical batch of ground lamb.*
Flavor: Varies depending on where the meat is taken from. In my experience, however, the variation in flavor of pre-ground lamb is far less than that of pre-ground beef. When shopping for pre-ground lamb, I look for mince with plenty of fat in it, as fat is largely what gives different types of meat their distinctive flavor. Also look for meat that is not packed too tightly. If it looks like a dense, wet, solid block in its packaging, it'll come out dense, wet, and solid in your burger. Good minced meat should be in loose packaging with an almost fluffy appearance.
I'm not positive of the reason why, but my guess is simply consumer knowledge and demand—everyone uses ground beef, and many people like their ground beef lean, so fat gets trimmed away and it's sold that way. Ground lamb users, on the other hand, place no such demands on butchers, so more fat makes it into the mix. Just a theory. Any meat packers out there know for sure? Meat guy?
Leg of Lamb ($10 - $15/pound)
Location: The hind legs.
Fat Content: Moderate. Depending on how well it's trimmed, it can range from virtually fat free to moderately fatty.
Flavor: Clean, mild, and rich. It's the most popular relatively inexpensive cut for roasting, and boasts a clean, meaty flavor without being over-assertively lamb-y. The meat is quite tender, so when ground has the tendency to come across as a bit mushy.
Sirloin and/or Round ($10 - $15/pound)
Location: The sirloin comes from the back half of the animal, in front of where the rear thigh meets the body. The round is a large muscle group in the rear thigh. I've grouped them together here because when ground and tasted, they have very similar flavor profiles.
Fat Content: Very low.
Flavor: The least lamb-y cut I tested. It tastes of minerals with a very light, almost sour flavor to it. A bit of liveriness as well. Similar in that respect to beef sirloin or brisket.
Shank ($5 - $10/pound)
Location: The bottom joint of the legs.
Fat Content: Moderate to high.
Flavor: Very robust and rich, the funkiest cut on the animal. It's generally used for braising, where its large amount of connective tissue is an advantage, slowly transforming into rich gelatin. When ground for mince, it requires a large amount of meticulous trimming so as to avoid tough, inedible bits in the final mix.
Shoulder ($6 to $10/pound)
Location: The front shoulder of the lamb.
Fat Content: High.
Flavor: Very well balanced with a large amount of fat, a bit of sour grassiness, and plenty or rich, deep lamb flavor. The equivalent of the beef chuck, it similarly is the best single-cut piece for making burger meat out of.
The Best Blend
When I explored blending beef cuts (in my first ever Burger Lab post!), I found that the best way to make a well-balanced blend was to mix a few different cuts to make sure to hit the right balance of nutty/grassy/rich/game-y flavors. With lamb, it was no different. The very best blend I could come up with was a mixture of leg meat (with as much fat as possible trimmed into it) for a neutral background, some shank meat for its umami-rich funkiness, and a bit of round to hit those higher metallic, livery notes.*
For the record, asides from the ratio, this is pretty close to the blend used for the awesome lamb burger at The Breslin, which is a mixture of sirloin, shoulder, and leg.
That said, unlike with beef, in a side-by-side taste test between straight up ground shoulder and my best-effort blend (which, considering how annoying shank it so trim was quite an effort indeed), the shoulder fared quite well, so for the ease of it, I'm going to stick with shoulder 95 percent of the time. The other 5 percent? I'll go for a good quality pre-ground lamb. The stuff I tested here was Pat LaFrieda ground lamb sold at Eataly.
Grinding and Forming The Patties
There are a few keys to good grinding, and depending on your equipment and needs, you can grind in a meat grinder, a food processor, or even by hand (check out this complete guide to grinding here. But whatever method you use, there's really only a few things you have to remember:
#1: Keep Everything Cold
That means place the meat grinder in the freezer before using it (I store mine there all the time), and place the cubed, trimmed meat into the freezer for about 15 minutes before grinding, making sure the cubes are spread out and separated from each other on a tray. The exteriors of the cubed meat should be just beginning to harden up.
#2: Handle Gently
The worst thing you can do to freshly ground meat is massage it or press on it too firmly. That said, if you plan on cooking your burgers on a grill instead of a skillet (and for lamb, I generally prefer the grill), you'll have to at least pack it hard enough that it doesn't fall apart when you lay it down or flip it. I form patties by weighing out the meat onto a plate (six to eight ounce patties are a good size for the grill, where I want to have plenty of pink meat in the center), then gently pressing and shaping them with my hands, using a spatula to lift the finished patties onto a separate plate for seasoning.
Meat contracts as it cooks, and burgers cook more around their perimeter than they do in their center. Just like a corset being cinched around the waist of a Victorian lady, whatever's in the middle gets pushed up. At least in the case of a burger, this is not a good thing, resulting in the dreaded "golf-ball-syndrome," a all-too-familiar affliction that results in round, bulgy burgers.
To combat this, pre-shape your patties with a slight dimple in the center (like the patty on the right in the image above).
#4: Season Well, On The Exterior Only
The relationship between salt and meat is not one-dimensional, nor is it extremely complex. More like, say Harry Potter and Hermione rather than Bella and Edward. It not only affects flavor, but it can drastically affect texture, depending on how it is applied. If you, for example, were to season your meat before grinding it, or were to season your meat after grinding, then massage the salt into it, you end up with a dense, springy texture as the salt begins to dissolve proteins in the meat and cause them to cross-link with each other. For a sausage, this is a good thing. For a burger, where a looser, more tender texture is desired, it's not.
In other words, try and keep the relationship between salt and meat in your burgers as simple as possible by only seasoning the exterior of the patty, though do season it generously. Remember, just like with a steak, you need to add enough salt to compensate for the fact that the interior of the burger will remain completely unseasoned.
And what about other flavorings?
Ok, fine. So you want to add other things to your lamb burger besides lamb? Go ahead, I won't stop you. Cumin, garlic, rosemary, mint—whatever you'd like. But if you're going to do it, do it right! Rather than adding the flavorings to the already-been-ground meat thereby forcing you to massage and overwork it, you're far better off starting with cubed chunks of lamb, seasoning them with your mix-ins, then grinding them all together. This'll get them evenly incorporated while still maintaining a nice, loose texture.
With grilling burgers, it's all about getting maximum charred crust, while maintaining a nice, pink, juicy core, which means in most respects, grilling a thick burger is exactly like grilling a thick steak. When I'm feeling lazy, I'll cook my burgers directly over the hot side of a two-zone fire, all while flipping multiple times to get fast, even cooking.*
You do know that those "flip only once folks" are lying or at least sadly misinformed, right?
If I want absolute perfect results, I'll start the burgers over the cooler side until they get up to around 90 to 100°F, then finish them off on the hot side until they hit 125 to 130°F for a nice, pink, medium rare.
Lamb fat, by the way, is a hard, waxy fat that—at least for my taste—is best when hot enough to melt and drip, which means that a rare lamb burger is right out for me.
Here's one thing you never want to see happening on your grill:
I mean, it looks cool and all, but what's really going on there is that your lamb fat is dripping off your burger, hitting the hot coals below, vaporizing, then igniting. Unlike coal, which is a clean burning fuel, lamb fat burns dirty. Rather than simply heating your burger, it ends up depositing nasty, sooty, black/gray crap on your patty. Small flare-ups are ok. Food-engulfing flare-ups should be avoided.
The best way I know of to control flare-ups is to starve them of oxygen. Cover up the grill and close all the vents. The fire should die down within seconds. Moving the food away briefly should also help.
The thing not to do is squirt at the coals with a water bottle, as the chances that you'll disturb sooty ash and have it fly up into your food is too great a risk.
Even after years and years of burger making, I still pull this one occasionally:
Oops. Yeah, that's what happens when you size your patty according to the raw meat-to-bun ratio, which is totally different from the cooked-meat-to-bun ratio. If you want your burger to fit your bun, make sure that when you form it raw, it overhangs the edges by about half an inch on all sides so that it'll shrink down to the right size as it cooks.
Condiments and Construction
If everything has gone right so far, you've managed to produce the Cadillac of lamb burgers. The last thing you want to do is mess it all up with a gaudy paint job. I like to apply condiments wisely, and sparingly.
The lamb burger at the Breslin comes with a thin slab of feta cheese, thinly sliced red onions, and a cumin mayonnaise. I like that combo up to the cumin bit, which to me is a bit over-aggressive, like the fuzzy dice of the burger world. Rather, I used plain old homemade Two-Minute Mayonnaise with a bit of garlic thrown in.
I'm almost never a fan of ketchup on a burger,* and doubly so with a lamb burger.
Nick Solares makes a good case against ketchup here.
Still not convinced lamb burgers can be every bit as tasty as a regular hamburger? All I can say is... baa.