Place foil grilling bag on cookie sheet. Sprinkle 1 tablespoon of flour in bag. Arrange steaks in single layer on top of flour; top with pepper and onion. In a small bowl stir together tomato sauce, Cajun seasonings, and remaining 2 tablespoons of flour. Spread evenly over steaks and vegetables. Seal bag by double folding open end, leaving room for expansion.
Coat grill rack with nonstick cooking spray. Preheat grill to medium indirect heat. Slide bag from cookie sheet onto grill rack. Cover and grill for 35 minutes. Remove bag from grill. Use kitchen shears to carefully cut open bag. Fold back top for steam to escape. Spoon steaks and vegetables over rice. Serves 4
