Sugar-glazed doughnuts are best eaten the same day.
Dough scraps can be reused, but reworked dough does not make for as smooth and perfect doughnuts.
Heat the oven for about 2 minutes or until just warm. Turn it off, but leave oven light turned on. Place a cup of very hot water with the bowl or baking sheet containing dough. Leave to rise as indicated in recipe.