Mini Meatball Pasta Bake

In a bowl, mix together the sausage, beef, oats, 1/2 of the Parmesan, egg, half the parsley, and salt and pepper until well combined. Form into small meatballs (about 1/2 inch) and brown in batches in a skillet over medium heat. Remove the meatballs from the pan and drain. Add the onions and garlic to the skillet and cook for 3 to 4 minutes, stirring occasionally. Add the tomatoes with juice, tomato paste, salt and pepper, sugar, and water. Stir and bring to a simmer, then add in the meatballs and continue simmering for 20 minutes. Remove the skillet from the heat and allow it to cool. Stir in the basil once cool. In a casserole dish, add half the pasta, half the mozzarella cubes, 1/4 cup Parmesan, and half the meatball sauce. Repeat with another layer, ending with the meatball sauce. Cover with foil and either refrigerate for up to 2 days, or bake in a 350 degree oven for 20-25 minutes. Serve piping hot!