1Peel off the papery skin from 1 pound of tomatillos and cook in 2 cups boiling salted water for about 10 minutes. Drain, reserving the cooking water.
2Blend the tomatillos, 2 seeded jalapeños, the leaves from 1 bunch cilantro, 2 cloves garlic, and 1 coarsely chopped white onion with about 1/2 cup of the cooking water until smooth. Transfer to a bowl.
3Toast 1 cup raw pumpkin seeds in 1 tablespoon lard or oil. Blend with 1 cup chicken stock until smooth. Combine both mixtures.
4Melt 2 tablespoons lard or oil and fry the tomatillo–pumpkin seed mixture for 3 minutes, or until bubbling hot. Season to taste with salt. Serve with chicken enchiladas or tacos. Makes 1 quart sauce.