In a large pot, bring salted water to a boil. Add pasta and cook until al dente, about 8-10 minutes. Reserve 1 cup of pasta water, drain, and set aside.

In a large skillet, heat olive oil over medium heat. Add minced garlic and sauté for 1 minute. Add sliced mushrooms and cook for 5-7 minutes until softened.

Lower the heat and add heavy cream, stirring continuously. Let it simmer for 3-4 minutes until it thickens slightly.

Combine the drained pasta with the creamy sauce, mixing gently. If the sauce is too thick, add reserved pasta water 1 tablespoon at a time.

Remove from heat and stir in Parmesan cheese if using. Garnish with parsley and serve immediately.