Sea salt to taste Put the unpeeled tomatoes, garlic, and chilies into a blender jar and blend until almost smooth; there should be a little texture to the sauce. Set aside. Trim the livers of any connective tissue and any greenish spots from the bile duct; cut each one into six parts. Heat the fat in a frying pan, add the liver pieces and onion, sprinkle lightly with salt, and fry, tossing them almost constantly a stir-fry if you willfor about 3 minutes over high heat. Add the blended ingredients and, still over high heat, cook for about 5 minutes or until the sauce has reduced and seasoned. Adjust seasoning. The Art of Mexican Cooking From the collection of Jim Vorheis