In a saucepan add 1 stick of unsalted butter, 16 ounces of heavy whipping cream, and 2 ounces of cream cheese.
Sauté until the butter melts completely.
Add in 3/4 cup grated parmesan cheese, 1/2 teaspoon of black pepper, 1/4 teaspoon of salt, and 1 teaspoon of garlic powder.
Simmer all for 15 minutes.
Meanwhile, on a skillet, sauté sliced mushrooms. Add about 1 teaspoon of salt. Mix occasionally, until mushrooms brown up.
Add mushrooms to the rest of the ingredients in the simmering pot. Turn heat off.
Combine with the pasta and serve!