1. Dice red and yellow bell peppers, slice asparagus diagonally, blanch them and set aside
2. Place bread slices on the baking tray, smear ketchup, and then spread a layer of shredded cheese
3. Then put the tuna meat, then red and yellow bell peppers and asparagus
4. Spread a layer of shredded cheese, preheat the oven to 200 degrees, and bake for 10 minutes until the cheese is melted.
