Heat chilis on the stove until they burn and blister. Put in cold water and put something heavy over them like a plate, and soak for one hour. Remove from water, straining and reserving the water. Discard stems and most seeds, then put into small food processor and process into a paste. Set aside.
Prepare the Meat
Heat a heavy skillet and melt the fat in it. Put in the onion and garlic and saute until the onions are translucent. Then add the meat. Brown on both sides. Remove from the pan and keep warm. Add the peppers and saute until they have softened a bit.
Put the meat back in the pan, and cover each piece with a little of the chili paste, turn and cover the other side of the meat with the paste. Cover and cook on low for about 5 minutes.
Add the chicken stock and the reserved chile water, and half of the cilantro.
Simmer uncovered until the liquid has reduced by half, then add the tomatillo, cilantrom ,and cook, uncovered until the liquid has reduced by half again.
The meat is done when it is fork-tender. Take a fork and pull the meat apart, and stir it well into the sauce.
Serve with tortillas and rice.
Notes
You don't have to use yellow bell pepper, use whatever you have on hand or what you can find at the market for a decent price.If you cannot find tomatillos, use salsa verde. That's what I usually do and don't have to bother with chopping cilantro. Herdez is a good brand.
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