Active Time

　　1 hr

　　Total Time

　　3 1/2 hr

　　In Chalcatongo, Jiménez purchases pit-roasted lamb, then warms up the meat in a simple tomatillo sauce rich with the earthy zing of costeño rojo chiles. On this side of the border, you'll have to cook your meat first, but our adaptation (we slow-roast it) couldn't be easier.

　　

Ingredients

Makese 6 to 8 servings

　　1/4 ounce dried avocado leaves

　　4 lamb shanks (about 4 pounds total)

　　2 oz dried costeño rojo chiles, wiped clean

　　2 1/4 pounds fresh tomatillos, husked and rinsed

　　2 garlic cloves, coarsely chopped

　　2 1/2 cups chopped cilantro

　　2 tablespoons vegetable oil

　　

Accompaniment:

warm corn tortillas

　　

Step 1

Preheat oven to 300°F with rack in middle.

　　

Step 2

Put avocado leaves in bottom of a heavy medium pot with a tight-fitting lid. Sprinkle lamb shanks all over with 2 teaspoons salt and arrange in pot (they don't have to be in 1 layer). Roast, covered, until meat is very tender, about 3 hours.

　　

Step 3

Meanwhile, slit chiles lengthwise, then stem, seed, and devein. Tear chiles into roughly 1-inch pieces (you should have about 1 1/2 cups). Heat a comal or large heavy skillet (not nonstick) over medium heat until hot, then toast chiles, stirring constantly, until more pliable and slightly changed in color, 1 to 2 minutes. Transfer to a bowl. (Chiles will crisp as they cool.)

　　

Step 4

Cover tomatillos with water in a medium saucepan and simmer, uncovered, until tender, about 10 minutes. Drain well, then purée with chiles, garlic, cilantro, and 1 1/2 teaspoons salt in a blender (in batches if necessary) until chiles are ground to small flecks.

　　

Step 5

Transfer shanks to a cutting board to cool. Strain lamb juices remaining in pot into a glass measuring cup. Let fat rise to top and skim off. Coarsely shred meat, discarding bones.

　　

Step 6

Heat oil in a heavy medium pot over medium-high heat until it shimmers, then cook one fourth of tomatillo sauce (it will spatter), stirring, until slightly thickened, about 2 minutes. Add remaining sauce and lamb juices and simmer, stirring occasionally, 10 minutes. Add lamb. Thin sauce with water if necessary. Simmer, stirring occasionally, until heated through, about 4 minutes.

　　Cooks' notes:

　　·Lamb can be roasted and shredded 3 days ahead and chilled. Chill juices separately; discard solidified fat.

　　·Lamb in sauce can be made 2 days ahead and chilled (covered once cool).