- 1/2 as much granulated sugar as you need powdered sugar
Pour the granulated sugar into the bowl of a powerful blender or food processor. You don’t want to do this in a cheap or old appliance because it probably just won’t get fine enough. Blend until the sugar is fine, fluffy, and powdered. Keep the lid on until the powder has completely settled.
If using right away, sift before adding to a recipe. If storing for later, add in 1 teaspoon of cornstarch or arrowroot then sift the sugar into a storage container. This helps prevent the sugar from caking and clumping.