1 1/2 lbs. lean round steak
1 tbsp. lime juice
4 cloves garlic, minced
1/2 tsp. salt
1/8 tsp. pepper
1/4 c. chopped onion
1/2 c. chopped tomato
1/2 c. chopped fresh cilantro
Vegetable cooking spray
12 (6 inch) flour tortillas
1 1/2 c. shredded lettuce
Chunky Guacamole
3/4 c. low-fat sour cream (optional)

Partially freeze steak; slice diagonally across grain into 1/4 inch strips, and set aside. Combine next 4 ingredients. Add steak; stir to coat. Cover and refrigerate 6 to 8 hours; stir twice. Mix onion, tomato, and cilantro in a small bowl, stirring well. Cover and refrigerate at least 1 hour.

Coat a large, heavy skillet with cooking spray; place over medium high heat until hot. Add steak; stir-fry 5 to 6 minutes, turning frequently.

Wrap flour tortillas in aluminum foil, and heat at 325 degrees for 15 minutes. Wrap tortillas around equal portions of steak. Sprinkle each fajita with 2 tablespoons lettuce. Top lettuce with 1 tablespoon each of reserved tomato mixture, guacamole and sour cream.