Preheat the oven to 180 C / Gas 4. Put on a pan of water for the pasta.
Brown the meatballs in a wok or deep frying pan, add the onion, garlic, courgette and mushrooms. Heat for 5 minutes.
Add the red pepper slices and tin of chopped tomatoes. Stir in the herbs and simmer for 15 minutes.
When the water is boiling add the pasta and cook to taste. Drain the pasta and set to one side.
In a saucepan, melt the butter and add the flour to make a roux. Add the milk and bring to the boil, stirring continuously. Add the 100g grated cheese.
Place the meatballs, veg and tomato based sauce in an ovenproof dish. Stir the cooked pasta into the cheese sauce. Cover the meatballs with the cheesy sauce. Sprinkle the remaining cheese (25g) over the top.
Bake in the oven until cheese is melted. Serve and enjoy!