They are deep fried and sprinkled with powdered sugar. It is also used for dusting confections in a manner similar to powdered sugar. The top layer is coated with a sprinkling of powdered sugar. Croustillons are deep fried dough balls served hot and liberally sprinkled with powdered sugar. They often come covered with powdered sugar or other toppings. They are often served with dusted cinnamon and powdered sugar. They are typically sprinkled with powdered sugar. Oliebollen are usually served with powdered sugar. The whole pastry is then covered with powdered sugar. This version may be garnished with powdered sugar. Covering cakes with powdered sugar or other materials was introduced in the 17th century. NHDC in pure form is found as a white substance not unlike powdered sugar. Traditional sufganiyot are usually filled with jam and covered with powdered sugar. It consists of thin puff pastry and often topped with powdered sugar. Apple strudel is traditionally served in slices, sprinkled with powdered sugar.