1/2 c. olive oil
1/3 c. lime juice
1/4 c. red wine vinegar
1/3 c. finely chopped onion
1 tsp. sugar
1 tsp. dried whole oregano
1/2 tsp. salt
1/2 tsp. pepper
1/4 tsp. ground cumin
3 cloves garlic, minced
2 lb. flank or skirt steak
8-12 flour tortillas

Combine first 10 ingredients in a shallow dish and stir well. Pound steak to 1/4 inch thickness. Add steak to marinade, turning to coat both sides. Cover and refrigerate 8 hours.

Remove steak from marinade; drain well. Grill steak over medium coals 6-7 minutes on each side. Slice into thin slices. Warm tortillas and wrap meat in tortillas. Add guacamole, salsa, etc.