Preparation
Clean the beef heart thoroughly, removing all nerves and fat.
Cut into 1" cubes, place in non-reactive bowl, refrigerate and set aside.
Combine garlic, chiles, cumin, oregano, salt and pepper and 1 1/2 cups vinegar.
Pour over meat. Add more vinegar, if necessary, to cover meat completely.
Marinate, refrigerated, 12-24 hours.
About 1 hour before grilling, remove meat from marinade and thread on skewers.
Reserve marinade. Soak the crushed chile in 1/3 cup warm water for 30 minutes.
In processor, combine chiles and water with oil and salt.
Add enough reserved marinade (3/4 cup) to make thick sauce, puree.
Brush skewered meat with sauce and grill over hot coals or under a broiler, turning and basting to cook quickly on all sides.
Best cooked medium well, 4-6 minutes on the grill.
Serve with remaining sauce for dipping.
