Preheat the oven to 350 degrees.

Cook the pasta according to the package direction. Drain and reserve 1/2 cup of pasta water. Set aside.

In a large skillet melt the butter over medium heat. Add the onion and saute for 3-5 minutes or until it begins to soften. Add in the garlic and cook for 1 minute.

Reduce heat to medium low and stir in the pumpkin, cheddar cheese, pepper jack cheese, and heavy cream or milk.

Stir frequently for 2-3 minutes or until the cheese has melted and mixes with the sauce ingredients.

Stir in the nutmeg, thyme, salt, and pepper. Add in more pumpkin if your sauce is too thin or reserved pasta water if it is too thick.

Remove from heat and stir in the cooked pasta. Toss to coat.

Pour the pasta mixture into a 9 x 13 pan. Set aside.

In a small bowl melt the butter. Stir in the breadcrumbs, garlic powder, and black pepper. Mix well.

Sprinkle the breadcrumb mixture over top of the pasta.

Bake for 20-25 minutes.

Serve hot.