This baked pizza spaghetti is one of my family's favorite spaghetti meals. It earned its name due to the ingredients are the variety you might enjoy on a loaded-up supreme pizza but, in the form of gooey baked spaghetti. Spaghetti noodles, cooked to al dente are covered with a meaty spaghetti sauce that includes sliced mushrooms, diced onion and bell pepper. It's layered with lots of mozzarella cheese and pepperoni, then baked until bubbly and golden.