To prepare an upside down pizza pot pie recipe, first you need to prepare your ingredients. In a large skillet, heat the olive oil over medium-high heat. Add the onion and cook until softened, about 5 minutes. Stir in the garlic, salt, pepper, and thyme. Cook, stirring frequently, until the onions and garlic are lightly browned, 2 to 3 minutes more. Remove the skillet from the heat and add the tomato sauce. Simmer, uncovered, for 30 to 40 minutes, or until thickened and bubbly. Serve with sour cream and parsley.