Preheat oven to 350 degrees.Boil a package of spaghetti as directed and drain. Next spray your casserole dish with cooking spray.
Add the cooked pasta to the casserole dish. Next add your favorite pasta sauce. Then add as many pepperoni slices as your heart desires. Then top of with shredded cheese - again whatever kind you like and as much as you want.
Bake uncovered for 30 to 40 minutes. Is that not the easiest and perhaps cheapest thing ever? And did I mention it is pretty darn good?