Preheat oven to 180°C. Slit pizza base from the centre and keep top half on the side.
Apply white sauce on lower part of pizza base and cover it up with the top half. Spread pizza topping on pizza base, sprinkle cheese and top it up with onion, tomato, capsicum and sweet corn.
Bake for 8-10 minutes or until cheese melts & pizza base turns light brown in colour. Season with chilli flakes & oregano. Cut into 4 pieces and serve hot.