In a large pan, on high heat add oil and sauté the onions, then add garlic, parsley, and Spinach, cook until all the moisture is then reduced.
In a pot with cooked tomato sauce, reserve 1 cup, set aside.
Add cooked sausages and pasta, mix well, add Parmesan Cheese, and mix until all combined.
In a large baking dish, add meat sauce, spreading evenly, add 6 slices provolone cheese, and sautéed spinach, add remaining pasta, and top with reserved tomato sauce.
Place in oven for 30 minutes, until cooked to desired preference.