Preheat oven to 420.
Place pre-made pizza crust on pizza pan.
Spread pizza sauce evenly around the pizza crust.
(Optional) Sprinkle chopped onion on the pizza sauce.
Cut Jarlsburg cheese into pieces less than 1/4 inches thick.
Cover the pizza as evenly as possible with your cheese.
Bake in oven for 12 minutes.
Slice and serve.