Brush each flour tortilla on 1 side with lime juice. Mix chili powder, ground cumin, and salt. Sprinkle seasoning mixture over lime-moistened side of tortillas. Cut tortillas into quarters.
Arrange quarters in a single layer, chili side up, on a 12- by 15-inch baking sheet. Bake in a 400° oven until chips are crisp and lightly browned, about 10 minutes.
