Cover a baking sheet with aluminum foil and coat with cooking spray. Arrange the fillets in a single layer on the foil. Brush the outside of each fillet with a light coat of olive oil.
In a small dish, combine the garlic powder, onion powder, ground black pepper, salt and Italian seasoning. Sprinkle the fillets with the seasoning mixture. Carefully turn the fish over and repeat with a coating of olive oil and seasoning.
Place one slice of fresh mozzarella on top of each seasoned catfish fillet. Place one slice of tomato over the mozzarella cheese. Bake the fillets at 350 degrees for 15-20 minutes until the mozzarella is melted and the fish is opaque and flakes easily with a fork.
Just before serving, sprinkle the top of each catfish fillet with the fresh basil. Drizzle the balsamic vinegar over the top.