- 15 minutes
- 1 hour
- 8 to 10
- Thoroughly butter the bottom and sides of an 11x15-inch baking dish.
- Place the uncooked pasta spirals in the bottom of the dish. Add the onions.
- Spread the cheddar and Swiss over the pasta and onions.
- Add the salt, pepper, and garlic powder, then add the milk.
- Bake in a 385-degree oven for approximately 50 minutes, stirring occasionally during the baking process.
- Add the mozzarella cheese and bake for an additional 5 to 10 minutes or until the cheese is melted.
- Serve warm.