Preheat oven to 450° F.
While oven is preheating, spray baking tray with cooking spray.
Place tortilla on the tray.
Add sauce. You can add more or less than suggested, but keep in mind that the tortilla will get soggy if you add too much liquid.
Add mozzarella cheese. Use more or less, depending on how much cheese you like.
Add parmesan cheese.
Add any other toppings you like.
Once you have finished topping your pizza, place tray into preheated oven for about 5 minutes (or until cheese has melted).
I like to switch my oven over to broil after this to get some extra crispiness, but this step is optional. I usually do this for around 1 minute, but keep a close eye on it to make sure it isn't burning.
That's all! Slice up and serve.