Frosting not Light and Fluffy?

Patience, grasshopper! Although the frosting may be smooth and creamy after just a minute of whipping, it takes much more time for it to take in enough air to become lighter in texture. Give it a solid 5–10 minutes before panicking, and if that doesn’t do it, you may want to add a teaspoon or two of water if it seems too thick, or ½–1 cup more confectioner’s sugar if you think it might be too thin. Make sure that you have the whisk attachment installed in your stand mixer, and crank it up to high.