Need powdered sugar now? Blend 1 cup white sugar with 1 tablespoon cornstarch until very fine. Sift it for smooth frosting.
Powdered sugar = 1 cup white sugar + 1 tbsp cornstarch (blend very fine)
Good for glazes, frosting and dusting. Let the dust settle before you open the blender. It may not get as fine as store-bought, so sift it for smooth frosting.