To cut down on steps and ingredients needed, I used a roasted garlic and herb-y store-bought tomato sauce. If you're not using one with a bolder flavor, you can add dried basil, parsley, oregano, garlic powder, etc. to the sauce before using for extra flavor.
You can use mild Italian sausage if you don't want this dish to be spicy. OR if you can only find mild sausage and you like spicy, add crushed red pepper flakes to the sauce to fit your tastes.