Cook the Pasta: In a large pot, bring salted water to a boil. Cook 12 ounces penne pasta until al dente, about 10-12 minutes. Reserve ½ cup pasta water, then drain and set aside.

Brown the Sausage: In a large skillet, heat 2 tablespoons olive oil over medium heat for 1-2 minutes. Add 12 ounces sweet Italian sausage, breaking apart, and cook for 5-7 minutes until browned.

Sauté the Garlic: Add 3 minced garlic cloves to the skillet and sauté for 1 minute. Stir to combine with sausage until fragrant.

Create the Sauce: Stir in 1 cup canned pumpkin purée, 1 cup chicken broth, and ½ cup heavy cream. Season with ½ teaspoon nutmeg, salt, and pepper. Simmer for 5-7 minutes.

Combine the Pasta and Sauce: Add drained penne to the skillet and toss with the sauce. Add reserved pasta water if the sauce is too thick.

Finish with Cheese: Remove from heat and fold in ½ cup grated Parmesan cheese. Adjust seasoning as needed.

Serve and Garnish: Spoon onto plates and garnish with parsley and red pepper flakes. Serve immediately.