Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1      kilogram      pork steaks
  10                    single pasilla peppers
  10                    single guajillo peppers
     1/2  clove         garlic
     1/4  cup           white vinegar
     1/4  teaspoon      cumin
   5                    single cloves
   1                    single salt; to taste
   1                    single onion; finely minced

Preparation:

Wash the peppers (removing the seeds), and boil in the vinegar until the peppers are soft. Blend the peppers, garlic and other spices in the same vinegar until you get a paste. Add more vinegar if necessary. Re-cook the past until it boils, continuously stirring to avoid sticking. Be careful, it gets very hot and might spatter while boiling. Get 1 kg pork steaks. The cut does not matter, but it has to be very thinly sliced. Ask your butcher to cut it and if possible to pound it flat. Thinly spread the paste on each steak and reserve the excess marinade. Put the steaks on top of each other, like in the "trompo" and let the meat marinate for 5 hours. (You can save the rest of the marinade for more meat, it does not spoil for long periods of time). In a hot pan or skillet partially cook one steak at a time. Use oil if necessary. Cut the meat in strips 1/4 cm thick, and finish cooking the meat with one finely minced onion. The unique aroma will let you know when they are ready.