Don't confuse weight and volume ounces when it comes to measuring your powdered sugar. Know just how much you're buying.
Everybody knows that 1 cup equals 8 ounces, right? Well actually, when weighing out ingredients for a recipe, 1 cup does not always equal 8 ounces. We know that 1 cup of water weighs 8 ounces, but honey, as an example, is thicker than water, so 1 cup of honey actually weighs in at 12 ounces.
Powdered sugar right out of the box or the plastic bag weighs 4 1/2 ounces per cup, so a 1-pound box (or 16 ounces) contains about 3 1/2 cups of powdered sugar. If a recipe calls for sifted powdered sugar, weigh out 4 ounces of sifted powdered sugar to equal 1 dry measuring cup. Sifting powdered sugar makes it lighter and fluffier, so it takes up more space in the cup.
Try these yummy Lemon Shortbread Cookies made with powdered sugar.