In a food processor, knead the ingredients together except the butter until the dough mixes, then stir in the butter and knead for 5 minutes. Cover and let stand for 1 hour, then degas and place in the fridge overnight. After resting, put the dough on a well-floured work surface and roll it out to a thickness of 2cm, cut out rounds with a 7cm cookie cutter, place them on a large floured work surface or on baking paper, spacing them out, cover and let rise for 1 hour (they should double in volume) then cook them on each side in oil heat to 180*C. Drain the fritters and then coat them with white sugar.