Bring a large pot of generously salted water to a rolling boil. Add the penne pasta and cook for 8-10 minutes until just barely al dente. Before draining, reserve one cup of the starchy pasta water, then drain the pasta completely in a colander.

Heat the olive oil in a large skillet over medium heat until it shimmers. Add the diced onion and cook for about 5 minutes, stirring occasionally, until the pieces become soft and translucent with golden edges.

Add the ground turkey to the skillet, breaking it into small crumbles with your wooden spoon. Cook for 6-8 minutes until no pink remains and the meat develops a nice brown color. Season with salt, pepper, and Italian seasoning, then stir in the minced garlic and cook for one more minute until fragrant.

Sprinkle the flour evenly over the turkey mixture while stirring constantly to prevent lumps from forming. Cook for one minute to eliminate that raw flour taste. Slowly pour in the chicken broth and tomato sauce while stirring continuously, then bring everything to a gentle simmer and let it thicken for 3-5 minutes.

Fold the cooked pasta into the sauce, making sure every piece gets coated. Stir in the half-and-half for that signature creaminess, and if the sauce seems too thick, add the reserved pasta water a few tablespoons at a time until you reach your desired consistency.

Reduce the heat to low and add half of both cheeses, stirring until they melt into the sauce and create that gorgeous, creamy texture. Turn off the heat, sprinkle the remaining cheese on top, and cover the skillet for 2-3 minutes to let everything melt together. Garnish with fresh parsley and red chili flakes before serving warm.