Place sliced fajita meat and prepared marinade in bag and refrigerate for 6 hours. Drain marinade and discard. In large, nonstick frying pan, heat oil. Add meat. Cook for 2 minutes. Add onion and pepper. Cook for 3 minutes, turning frequently.

Remove from heat and place in warm tortilla. Sprinkle with cheese and tomato. Add sour cream and picante sauce.