Lay chilies and beef on a barbecue grill over a solid bed of hot coals or on a gas grill over high heat (you can hold your hand at grill level only 2 to 3 seconds); close lid on gas grill. Turn chilies as needed to brown and blister all sides, 5 to 7 minutes. Cook beef, turning once, until browned and rare in center of thickest part (cut to test), 8 to 10 minutes, longer for medium or well done. Pull stems, seeds, and skins off chilies and discard. Coarsely chop beef and chilies, and mix together. Add salt and pepper to taste. Use warm or cool.
Nutritional analysis per 1/2 cup.