Combine tomatoes, onions, peppers and chiles; mix well. Chill.
Combine barbecue sauce, lime juice, Worcestershire sauce, tequila
and cumin; mix well. Pour over steak. Cover. Marinate in refrigerator
several hours or overnight.
Drain, reserving marinade.
Grill uncovered 10 to 15 minutes or to
desired doneness, brushing frequently with marinade and turning
occasionally.
Carve across grain into thin slices.
Serve with tomato mixture, tortillas and sour cream.