As a half-Jew, half-Protestant, I might claim to be uniquely qualified to offer a spring lamb recipe—after all, it's a significant meat for both Easter and Passover. But who am I kidding? I'm as secular as they come. Being a good cook will have to suffice as my authority here.
In deciding which cut of lamb to focus on, I thought about spring itself and what a transformative season it is, as the sun gives off a warmth it hasn't for months and the skeletal frames of trees flush with pink flowers and gray-green buds. It seemed like a similarly transformative cut was in order. Instead of popular lamb choices, like tender leg and chops, I settled on shanks. They start out tough as rubber, but, with the right approach, practically melt off the bone.
Shanks come from the lower portion of the lamb's legs and can be subdivided into two categories: foreshanks (from the front legs) and hind shanks (from the...wait for it...hind legs). Hind shanks tend to be meatier than foreshanks, but a single shank of either type is large enough to feed a person.
Those legs do a lot of work for the animal, which means that the shank meat is loaded with strong, collagen-rich connective tissue—a medium-rare lamb shank would be nearly impossible to chew. But with a long, slow braise, that collagen softens into unctuous, tender, lip-sticking gelatin. As in the stories of the Jews being freed from slavery in Egypt and Jesus transitioning from earthly to heavenly form, properly cooked lamb shanks undergo a divine metamorphosis.
The process for making them hews closely to the one we use for the tough cuts in other braises and stews.
I start by searing the shanks in oil until they're browned to develop and deepen their flavor. In this recipe, I rub them first with a spice mixture made from ground coriander, fennel, cumin, and smoked paprika, along with salt and pepper, of course; those spices add layers of flavor and complexity to the braise. Bone-in shanks can be awkwardly long and large, so you'll likely need to brown them in batches.
Once they're browned, I transfer the shanks to a baking sheet, then add a classic mirepoix of diced carrot, onion, and celery, plus some garlic, to the pot and cook it all until it's starting to brown all over. Toward the end, I stir in some tomato paste and anchovy fillets for richness. You won't taste any of the fishiness of the anchovies in the final dish; instead, you'll get a deeply savory flavor in each bite.
To stop the browning of the aromatics and scrape up all the dark bits that have formed on the bottom of the pot (called the fond in cooking-ese), I hit the pot with some dry white wine, then return the shanks to the pot along with some chicken stock. This is a braise, but I'm going for the lighter flavor of white wine and chicken stock so that the dish reflects the season better—deep, dark braises are on hold until next winter.
In a lot of our recipes on Serious Eats, we add unflavored gelatin to store-bought chicken stock as a way of introducing the gelatin that a good homemade stock always has. It helps improve a sauce's body and texture by increasing its viscosity. Here, I didn't need to bother, since the lamb shanks will contribute plenty of gelatin to the broth as they cook. If your stock is homemade and gelatin-rich (you'll know, because it'll gel when chilled), that's great, but if not, no need to worry.
At this point, the braise is ready to go into the oven. I take a similar approach to what we do for our beef stews, cooking it in a low oven set to 300°F. Higher heat will cook the meat and melt the collagen faster, but it'll also dry the muscle fibers out more. A gentler temperature delivers juicier meat.
I wanted some evaporation during the braise, so that the juices reduced and thickened, but I didn't want it to cook down too quickly. At the same time, I wanted the portion of the shanks above the liquid to brown and develop a deep, flavorful crust. The best way to get both is to partly cover the pot. You can do that by cracking the lid, but I'm also very partial to the parchment paper–lid technique. Simply cut a piece of parchment in a round just big enough to fit inside the pot, give it a center vent, and place it on top. It allows for just the right amount of evaporation and browning.
It's also important to turn the shanks once during the braise, so that the parts exposed to the hot oven air don't over-brown and dry out. Turning the meat also gives the submerged portions some time to peek out and develop their own share of good, browned flavor.
As soon as the lamb is tender, it's done. It's hard to be precise on time, since each cut and oven is different, but somewhere around three hours at this low temperature is about what it'll take.
To finish the dish, I pull the shanks from the braising liquid, then transfer the liquid and all the aromatics in the pot to a blender, blending it all into a smooth sauce—that vegetable fiber is an excellent thickener. If you have a high-powered blender, it'll do amazing work forming a smooth sauce all on its own. If you don't, you may want to pass the sauce through a fine-mesh strainer afterward to remove any grittier bits of fiber that are left behind.
Depending on how much liquid has evaporated during the braising, you may need to thin the sauce slightly with water or stock to adjust its consistency. Less likely, but also possible, is that it'll be too thin, in which case you'll have to reduce it in a saucepan.
I baste the shanks in the sauce, then serve them with a light, bright herb and endive salad, a promise of the sunny days ahead. (Although, perhaps better than the promise of springtime is the more immediate promise of all that marrow in those bones.)