Bring a large pot of salted water to a boil.

Meanwhile, cook the Italian sausage in a large, deep skillet over medium heat, breaking it apart as it cooks.

Once the sausage is browned and cooked through, drain the excess grease. Transfer the sausage to a plate and set it aside.

Add the gluten-free penne to the boiling water and cook for approximately 8 minutes, or until slightly firm. Drain the pasta without rinsing it.

In the same skillet used for the sausage, melt 2 tablespoons of salted butter over medium heat.

Stir in the heavy whipping cream and a pinch of salt.

Gradually add the shredded Parmesan cheese. Continue stirring over medium heat until the cheese is melted and the sauce is smooth.

Return the drained sausage to the skillet and stir it into the Alfredo sauce.

Add the drained penne and gently stir until everything is evenly coated.

If the skillet is not oven-safe, transfer the pasta mixture to a lightly greased casserole dish.

Sprinkle the shredded mozzarella evenly over the pasta.

Place the dish under the oven broiler for 2–5 minutes, or until the cheese is melted, bubbly, and golden.

Watch the dish carefully while broiling. Remove it from the oven and let it rest for a few minutes before serving.