Preheat oven to 425 degrees. Cut bacon slices into 3rds. Slice tomato into 3 slices. Butterfly chicken breasts cutting almost in half. Cut slices of cheese in half.
Lay 1 1/2 slices of tomato in each chicken breast. Top that with both halves of cheese placed end to end on each breast. Sprinkle each breasts on the inside with garlic and onion powders and pepper. Close chicken breasts. Sprinkle each breasts on top with small amount of rosemary or if using fresh pull off a couple leaves and place on top of each breasts. Lay bacon across each breasts. Tuck any overlay of bacon underneath breasts. Secure bacon with toothpicks.
Place breasts in shallow baking dish. Bake for 45 minutes. Remove bacon (and fresh rosemary leaves if used). Place chicken back in oven for additional 8-10 minutes to brown. While waiting for chicken, place any uncooked bacon in the microwave for a few seconds to completely cook. Serve chicken with crumbled bacon on top.