Pre-heat oven to 350°F . Grease a 9x13 baking dish and set aside. Cook pasta according to package instructions, drain and set aside.
In a large pot, heat butter and olive oil over medium heat. Add onion, and allow it to cook for 1-2 minutes stirring frequently to avoid scorching.
Add cream, milk, 2 oz of goat cheese, pumpkin and Parmesan.
Reduce heat to low, whisking continuously and allow the sauce to slowly bubble. Allow the sauce to cook for 7-10 minutes. The sauce should reduce a bit, but will not be thick (it will thicken in the oven).
Remove from heat and gently stir in the pasta and bacon.
Pour pasta into the prepared baking dish. Add ½ the bacon and stir. Top with remaining goat cheese and bacon.
Bake for 30-40 minute or until sauce is bubbly.