Begin by filling a large pot with water and adding a generous pinch of salt. Bring the water to a rapid boil over high heat. Once boiling, add 12 ounces of penne pasta and cook according to package instructions for 10-12 minutes until al dente. Just before draining, reserve 1/2 cup of the starchy pasta water. Drain the pasta and set aside while you prepare the sauce.

In a large skillet, heat 1 tablespoon of olive oil over medium-high heat. Once shimmering, add 1 pound of Italian sausage, breaking it up with a wooden spoon. Cook for about 5-7 minutes until the sausage is browned and cooked through.

Add 1 finely diced small yellow onion to the skillet with the sausage. Sauté for about 3-4 minutes until soft and translucent. Stir in 4 minced cloves of garlic for an additional 1-2 minutes until fragrant.

Incorporate 2 tablespoons of tomato paste into the skillet, stirring well for about 1 minute. Then add 1 can of crushed tomatoes, 1 teaspoon of Italian seasoning, 1/4 teaspoon of red pepper flakes, 1/2 teaspoon of salt, and 1/4 teaspoon of black pepper. Allow to simmer on medium heat for 4-5 minutes.

Reduce the heat to low and stir in 1 cup of heavy cream, mixing until the sauce is smooth. Let it simmer for about 2-3 minutes.

Mix in 3/4 cup of grated parmesan cheese until melted. Then, add the drained penne pasta, tossing gently to coat. Gradually pour in the reserved pasta water as needed to adjust sauce consistency.

Taste the sauce and adjust seasoning if needed. Remove from heat and sprinkle with freshly chopped parsley or basil. Serve immediately, garnished with extra parmesan if desired.