Heat a large pot over medium heat and add a splash of oil.

Toss in the diced bell pepper and red onion. Sprinkle with 1 teaspoon of salt. Sauté until softened and fragrant, about 5-7 minutes.

Add the pesto sauce directly to your sautéed vegetables, stirring to coat them well.

In a small bowl, whisk together heavy cream, flour, garlic powder, and oregano. Gradually pour this mixture into the pot, stirring continuously until creamy.

Add the remaining salt, black pepper, and a bit of the reserved pasta water to loosen the sauce as needed.

Gently fold your cooked penne into the creamy sauce until well coated.

Garnish with freshly chopped parsley and grated Parmesan, if desired.