Steps
1. Preheat the oven to 375°F (190°C).
2. Season the fish fillet with salt and pepper on both sides.
3. In a small saucepan, melt the butter over medium heat.
4. Add the ketchup and mashed peaches to the saucepan, stirring until well combined.
5. Place the fish fillet in a baking dish and pour the peach glaze over the top.
6. Sprinkle the shredded cheese evenly over the fish.
7. Bake in the preheated oven for 15-20 minutes, or until the fish is cooked through and the cheese is melted and bubbly.
8. Serve hot and enjoy!