The batter must be pre-baked, cooled, then re-trayed and topped, and cooked again for a final 5 to 10 minutes. A very hot pizza stone will ensure the best finish.
You can make and pre-bake the base ahead: it keeps in the fridge for 10 days layered with baking paper, and you can store it flat in airtight bags in the freezer too. Defrost in a single layer on a baking tray for 10 to 15 minutes before topping and baking.
Preheat oven to 180°C.
Place all the ingredients in the bowl of a KitchenAid or similar mixer with a K beater or paddle attachment. Mix at medium speed for about 5 minutes to make a batter. The ingredients can also be mixed by hand. Whichever method you use for mixing, the resulting batter will be fairly wet, the consistency of a thick cake mix.
Spoon the batter onto a tray lined with baking paper. Press another sheet of baking paper over the top and push the batter into a disc shape. The size of the pizza is up to you but the base should be about 1 cm thick. Bake for 10 minutes in a preheated oven. Remove from the oven and allow to cool. Repeat until all batter has been used.
Turn oven up to 220°C. Peel off the top sheet of baking paper, top pizzas with desired ingredients, then cook again for up to 10 minutes or until crisp.