1 Preheat oven to 375 degrees F2 Chop the onion, tomato, and lemon into thin slices3 Coat both sides of each fillet with olive oil4 Place fillets in a glass pan5 Sprinkle with salt and pepper6 Lay slices of onion, tomato, and lemon to cover the top side of each fillet7 Bake for 8 to 12 minutes