Pre-heat oven to 375°.  Mix meat, stuffing mix, chili powder, and water until well blended.  Spray muffin cups with cooking spray and press meat mixture into the cups.  Indent in the center with a spoon to form a cup shape.  Spoon in the salsa and bake for half an hour, or until the loaves are cooked through.  Top with the cheese and continue baking for 5 minutes or until cheese is melted.