HEAT oven to 400ºF.
PLACE tortillas in single layer on baking sheet; spray with cooking spray. Sprinkle evenly with 1 tsp. chili powder. Bake 7 to 8 min. or until crisp.
MEANWHILE, brown meat in large skillet. Add beans, salsa and remaining chili powder; cook 4 min. or until heated through, stirring occasionally. Remove from heat. Stir in half the cheese.
SPREAD meat mixture onto tortillas; top with remaining cheese, lettuce, tomatoes and sour cream.
