My wife, Adri, and I just got back from a week spent eating our way around Mérida and the rest of Mexico's Yucatán Peninsula. And when I say eating, I mean it. We kept a notebook and log and calculated that we each averaged one taco every four hours for the entire time we were there. And that's on top of the papadzules, the queso relleno, the cochinita pibíl, the ceviche, the relleno negro... you get the idea. It was a whirlwind, to say the least. A spicy, kind of plump, oil-slicked whirlwind that I never wanted to end.
Of all the things we ate, sopa de lima, the Mayan poultry and lime soup that's popular up and down the Yucatán, seemed most easily adaptable to cooking back home. It's also one of the simplest and most crowd-pleasingly delicious dishes we had. It was a no-brainer to make a couple of batches when we got back home to at least keep my mind and soul on extended vacation time.
Sopa de lima is not all that different from the tortilla soup you'll find in Mexican and Tex-Mex restaurants across the country. Both are made with a seasoned poultry broth and served with shredded meat and crisply fried corn tortilla strips, which add texture and flavor to the soup. But it's the subtle differences in flavoring that set them apart, starting with the broth.
Chicken may be the bird of choice for most of the world, but in much of Mexico, turkey reigns supreme. Every batch of sopa de lima I had in the Yucatán (not to mention countless salbutes and panuchos) was made with turkey, and, if I had my way, we'd all be eating turkey outside of sandwiches more than once a year in this country. Unfortunately, my local supermarkets and meat markets disagree with me—I couldn't find bone-in turkey breasts anywhere nearby and had to resort to using chicken instead. (This shouldn't stop you from using turkey in its place for a more authentic flavor.)
Typically, this broth would be made 100% from scratch—it's easy to do when you have turkey or chicken carcasses lying around from other uses, and if you've got homemade stock, you can use that, too. But I wanted to make sure that this recipe worked even without good homemade stock, so I start with boxed low-sodium chicken broth, which I pour over some split chicken breasts (again, turkey would be better!), along with a few aromatics. An onion cut in half, a few garlic cloves, and some bay leaves form the vegetable backbone. The spices are the first element that makes this soup truly unique.
Recipes I've looked up (like the excellent ones from Rick Bayless and David Sterling) differ in exactly which spices are used and how much of each. The versions I tasted in Mexico had a distinct clove-like aroma with a touch of cinnamon. (For this, it's important to seek out real Mexican canela, with its wispy, scroll-like bark and mild aroma, instead of cassia, the much more common Vietnamese cinnamon, with its thick bark and sharp bite.) Black peppercorns, allspice, and Mexican oregano round out the flavors for my broth.
To keep the chicken moist and tender, I use our cold-start poaching technique, which helps the chicken cook more evenly. I put all the ingredients in a pot, bring it up to a bare simmer, then reduce the heat until the broth is just steaming, allowing the chicken to gently cook while the aromatics steep. It takes about half an hour for the chicken to cook through—plenty of time to work on our sofrito.
In the Yucatán, I saw both clear versions of this soup, made with the broth alone, and deeper-red versions made with a sofrito. It's the latter version that spoke to me more. If the broth is the body of this soup, the sofrito is the jewelry and tattoos that give it character. Like a French mirepoix, a sofrito is a sautéed mix of vegetables used to flavor soups, stews, and sauces. Here's where sopa de lima gets its second jolt of unique flavor. Instead of simply chopping up the garlic and tomatoes for the sofrito base, I char them. And I mean really char them.
To do it, I thread whole, unpeeled cloves of garlic on a metal skewer—a wooden skewer will not work for this!—and hold them directly over the gas flame on my stovetop (if you don't have gas burners, you can toast the garlic in a dry skillet) until they're black on all surfaces and the skin starts to flutter off. Next, I do the same with a couple of Roma tomatoes (they go much faster). Once peeled, the garlic and tomatoes retain a distinctly smoky flavor from their charred skins, and that flavor carries through when I sauté them with onions and peppers. Bell peppers work fine, but I find that Hungarian wax peppers meld into the soup better.
The final element of sopa de lima is its namesake: the lima. Though lima translates literally as "lime," and though you would be forgiven for mistaking a Yucatecan lima (also called lima ágria—"sour lime") for a lime on first glance, limas have a distinctly sweeter, more floral aroma, with a slightly bitter aftertaste. Using straight-up lime juice simply won't cut it. It's pretty much impossible to find true limas here in the US, so some folks recommend using a combination of lime and orange juice. I find that lime and grapefruit juice is a little closer to the real deal. To really reinforce the flavor, I peel off strips of the grapefruit and lime zest and add them to the hot broth after straining it, letting them steep like a tea.
Once the sofrito and the steeped broth are ready, I combine the two and season the soup with salt. The only remaining ingredient is the tortilla strips. If you happen to have a fryolator hot and ready in your kitchen, you can deep-fry fresh corn tortillas cut into strips. For the rest of us, pan-frying with a little bit of oil will do the trick. It's hard to get the tortilla strips perfectly evenly crisp and cooked with this method, but we're going to be dunking them into wet soup* anyway, so perfectly even crispness is not a top priority.
Is there any other kind of soup?
To serve the soup, I shred up some of the chicken (all the while wishing it were turkey) and place it in the bottom of a warm serving bowl before topping it up with the hot broth and a handful of tortilla strips. A little chopped cilantro and some sliced limes finish it off.
It's an altogether simpler and more delicately aromatic affair than the filled-to-the-brim, avocado-black-bean-and-corn-stuffed bowls of tortilla soup you'll find at American chain restaurants. But you know what? If you want to go ahead and toss some diced avocado into that bowl, nobody is going to stop you.