1. Blended granulated sugar + cornstarch
1 cup
granulated sugar
1 tsp
cornstarch
Best swap: Blended granulated sugar + cornstarch. Use 1 cup granulated sugar plus 1 tsp cornstarch per 1 cup.
Powdered sugar (icing or confectioners' sugar) is just granulated sugar ground fine with a little starch to stop clumping. A blender lets you make your own.
Blend 1 cup of granulated sugar with 1 teaspoon of cornstarch on high for about a minute until it turns fine and powdery. Let the dust settle before opening the blender.
Not directly in icings, since it will not dissolve smoothly. Blend it fine with a little cornstarch first, or it will leave a grainy texture.