Step 1

Heat the vegetable oil in the pressure cooker pot over medium heat until the oil is shimmering. Add the onion, garlic, salt, and chile powder. Saute until the spices are toasted and the onions are softened, about 5 minutes. Pour in the beer, scrape the bottom of the pot to loosen any stuck bits of onion, then wait for the beer to come to a simmer, stirring occasionally, about 3 more minutes.

Step 2

Add the lamb to the pot, sprinkle it with 1 teaspoon of salt, then stir the lamb chops to coat them with the onions and spices. Pour the can of tomatoes and green chiles on top of the lamb, but don’t stir.

Step 3

Lock the lid on the pressure cooker and bring it to high pressure. Pressure cook on high pressure for 15 minutes (20 minutes for an electric pressure cooker), then turn off the heat and let the pressure come down naturally for 15 minutes. Quick release any remaining pressure in the pot.

Step 4

Remove the lamb to a platter (it should fall apart as you’re removing it from the pot), leaving as much of the vegetables behind as possible. Pour the cooking liquid and vegetables into a blender or food processor, and blend until completely pureed. (To keep the blender from overflowing with the hot liquid, remove the center cap from the lid and hold the lid on with a kitchen towel.) Pour the puree back into the pot and bring to a simmer over medium heat. While the liquid is simmering, shred the lamb using a pair of forks, discarding the bones and any large pieces of fat.

Step 5

Add the shredded lamb to the simmering liquid in the pot, and simmer until thickened, five to ten minutes. Taste the braised lamb, and add salt and pepper to taste. Serve with the tortillas and accompaniments.