Superfine Sugar (10X)

Superfine or 10X sugar (also known as Ultrafine, bakers, castor or bar sugar) is regular sugar that has been ground into a fine powder. It will dissolve easily into beverages and baking mixes. This differs from powdered sugar (or confectioner's sugar) because of the addition of cornstarch to prevent the powdered sugar from caking and powdered sugar is even finer.

If you have no powdered sugar, you can put some granulated (regular) sugar in a blender with a pinch of cornstarch and process it.