Begin by bringing a large pot of salted water to a rolling boil. Add the penne pasta and cook until just shy of al dente, about 8-10 minutes. Reserve 1 cup of pasta cooking water, then drain and set aside.

Heat 2 tablespoons of olive oil in a large skillet over medium heat. Add the diced yellow onion and sauté for about 5 minutes until translucent.

In the same skillet, add ground turkey and cook for 6-8 minutes, stirring occasionally. Season with salt, black pepper, and Italian seasoning, then add minced garlic and cook for an additional minute.

Sprinkle the all-purpose flour over the turkey and stir well. Gradually pour in the chicken broth and tomato sauce, bringing to a simmer. Cook for 3-5 minutes until the sauce thickens.

Gently fold the cooked penne into the skillet with the sauce, stirring in the half-and-half and reserved pasta water to achieve desired creaminess.

Reduce heat to low and fold in half of the mozzarella and cheddar cheese until melted. Top with remaining cheese, cover, and let sit for 2 minutes.

Plate the creamy Ground Turkey Pasta and garnish with freshly chopped parsley and red chili flakes, if desired.