Set the oven temperature to 220C/200 fan/gas 7 and add two baking sheets.
In a small saucepan, heat the oil and sauté the onion for 10 minutes over low heat, or until soft, to make the sauce. Bring the water, sugar, and chopped tomatoes to a boil before adding the purée. Reduce by half and thicken in a saucepan over low heat, stirring often for 25 to 30 minutes. Blend the sauce to a silky consistency using a hand blender. Add the basil once you’ve seasoned it to taste. Put the heat off for a while.
Mix the flour, sugar, baking powder, salt, and xanthan gum together in a large bowl to make the dough. Dig a well in the middle and fill it with 250 ml of warm water and olive oil. Mix the ingredients quickly with your hands until you get a thick, sticky paste. Add another 20 cc of warm water if the dough feels dry. Store for up to 24 hours in the fridge in a sealed container or dish before serving. Lightly flour two more baking sheets. Half of the dough should be pressed into a circle on the sheets, between 20 and 25 centimeters in diameter.
To finish the bases, spread a thin layer of sauce over them and sprinkle them with mozzarella cheese. To get crisp edges, bake the sheets for another 8-10 minutes on top of the hot sheets.
When it comes to the gluten-free flour mix
- 400 grams of gluten-free all-purpose flour
- 2 rounded teaspoons of light brown sugar
- Gluten-free baking powder, 2 teaspoons
- a pinch of table salt
- 1.25 g xanthan gum
- 5-tablespoons of olive oil
As a condiment and topping
- 1 tablespoon of olive oil
- a small onion, cut very finely
- (1 x 400 g can) chopped tomatoes
- Two tablespoons of tomato paste
- Caster sugar, one teaspoon
- 1/2 of a tiny bunch of basil; shredded leaves
- The equivalent of 2 × 125g buffalo mozzarella balls