Tomatillos are nearly essential to this recipe, but may be very hard to obtain outside of Mexico and the USA. You may be able to order seeds and grow them yourself; they require conditions very similar to tomatoes. If you cannot find or grow your own tomatillos, you can try substituting green tomatoes plus lime juice.
Put in a large ovenproof pot:
2 kg of broiler/fryer chickens, cut up or 2 kg of pork, cut into 3-cm cubes
450 ml chicken stock
Bring to a boil, reduce heat, cover and simmer until the chicken is tender – about 45 minutes. Drain, setting the stock aside, and keep the chicken warm.
Grind as finely as possible, in blender or mortar and pestle:
225 ml pumpkin seeds
Set the pumpkin seeds aside, and put into blender:
125 ml walnuts or pecans
125 ml almonds
1 large onion, chopped
1 clove garlic, chopped
400 g tomatillos –or- 400 g green tomatoes + 10 ml lime juice
8 poblano chile peppers, cored and seeded (may substitute jalapeños)
good handful of cilantro, chopped
salt pepper to taste
Blend to a coarse purée. You may need to process it a bit at a time in order to make a smooth mixture. Add the pumpkin seeds and blend well. Heat in a large skillet:
30 ml lard or oil
Add the purée and fry for 2-3 minutes. Add chicken stock, a little at a time, until the mixture is smooth and has the consistency of heavy cream. Pour the sauce over the chicken and cook over very low heat until the meat is very tender – about 15 minutes.