Preheat the oven to 350˚F.
In a large skillet, cook the meatballs in a drizzle of olive oil until cooked through. If you like, add some onion, pepper and/or zucchini to the pan along with the meatballs, cooking them until soft.
Stir in the tomato sauce.
Meanwhile, cook the rotini or penne until al dente, drain and pour into a baking dish.
Top with the meatballs and sauce, then scatter with cheese. Bake for about 20 minutes, or until bubbly and golden.