By hand, combine the yeast, sugar, lukewarm water and 25g of the flour in a large bowl. Leave to prove for 20 minutes in a warm place. Put the remaining flour, salt and olive oil in a bowl then add the yeast mix and combine with a wooden spoon, adding water as needed until a dough forms.
Turn out on to a floured work surface and knead for 7-10 minutes, until smooth and elastic. Put in a bowl, cover with cling film and leave to rise in a warm place for 1 – 1½ hours, until doubled in size.
Cut the dough into two portions. Roll them out into 3-5mm thick circles. Preheat two pizza trays, sprinkle them with a little flour, put the pastry circles on the trays. Spoon a layer of the sauce over the pastry, then dot with mozzarella, olives and oregano. Bake in a hot oven for 12 - 15 minutes.
For the sauce
Heat the olive oil in a large pan, add the pepper, whole chilli, passata and dried oregano and cook until reduced down to a sauce consistency.
