Fantastic Beef Fajitas Recipe

In a large resealable bag, combine marinade ingredients; add beef. Seal and refrigerate for 3-6 hours or overnight, turning several times. Discard marinade. In a skillet, saute onion and pepper in 1 tablespoon oil until crisp tender; remove from pan. Add remaining oil and saute meat until no longer pink, about 4 minutes. Add vegetables to pan and heat through. To serve, place a spoonful of meat/vegetable mixture on a warmed tortilla and top with avocado, salsa and sour cream. Roll tortilla around filling.