Step 1: In a large skillet, melt the butter over medium heat. Add the heavy cream and garlic powder (if using), and cook for 2-3 minutes, stirring frequently.
Step 2: Cook the penne pasta according to the package instructions until al dente. Drain and set aside.
Step 3: Reduce the heat to low and gradually whisk in the grated Parmesan cheese until the sauce is smooth and creamy. (test)