toppings of your choice, such as olives, sliced red onion, artichoke or ham (optional)
rocket leaves, to serve (optional)
400g tin plum tomatoes
1 tsp baking powder
4 sprays olive oil spray
陆 tsp salt
300驳/10陆辞锄 self-raising flour, plus extra for dusting
200g/7oz firm mozzarella cheese, grated
300驳/10陆辞锄 plain yoghurt