Preheat oven to 350 degrees Fahrenheit.

Place sausages in a roasting pan.

Roast sausages for 12-15 minutes, or until slightly golden and cooked through.

Remove sausages from oven and let cool slightly.

Cut sausages at an angle into bite-sized pieces.

Bring a large pot of salted water to a boil.

Add penne pasta to the boiling water and cook until al dente, according to package directions.

While pasta cooks, set a large, heavy-based pot over medium heat.

Add 2 tablespoons of olive oil to the pot.

Add chopped onion and garlic to the pot and sauté until translucent and fragrant.

Add crushed San Marzano tomatoes and torn fresh basil to the pot.

Season with salt and pepper to taste.

Simmer the sauce for 15 minutes.

Fold in heavy whipping cream and continue to simmer until the sauce is rich and creamy.

Add the cooked sausage pieces, blanched peas, and grated Parmigiano-Reggiano cheese to the sauce.

Fold all ingredients together and cook for 2-3 minutes to allow flavors to meld.

Drain the cooked pasta.

Add the drained pasta to the sauce and toss to coat.

Serve immediately, topped with a shower of additional grated cheese and garnished with fresh basil.