Preheat the oven to 200°C, 400°F, Gas Mark 6
Using an upturned glass or cookie cutter, cut rounds in the large pizza bases to make mini pizza bases.
Cover each circle with a spoon of tomato pizza sauce.
Place a piece of mozzarella, cubes of pepper and a few slices of mushrooms.
Sprinkle with Oregano.
Bake for 10 minutes.