Melt 2 tablespoons butter in a large skillet over medium heat.

Add 1 small diced onion and sauté until tender, about 5 minutes. Stir in 3 cloves minced garlic and cook until fragrant, about 1 minute.

Remove the skillet from the heat. Transfer the cooked onion and garlic to a blender. Add 24 oz roasted red peppers (2 jars, drained), 1 cup chicken stock (or vegetable broth), salt and pepper to taste, and 1/4 teaspoon dried basil. Blend until very smooth. If the mixture is too thick to blend smoothly, add a little of the heavy cream (from the 1/2–3/4 cup) a tablespoon at a time to help it move.

Pour the blended sauce back into the skillet and set the pan over low heat. Stir in 1/2–3/4 cup heavy cream. Warm the sauce gently, stirring occasionally, until heated through and slightly thickened. Do not let the sauce boil.

Add the cooked pasta (see ingredient list) and 3/4 cup grated Parmesan cheese to the sauce. Toss until the pasta is evenly coated and the cheese is melted.

Taste and adjust salt and pepper as needed.

Serve immediately.