How to make icing for sugar cookies with powdered sugar

Grab the thinner flooding icing and drizzle the icing all over the inside of the cookie. Since it's thinner, it will spread to fill most of the cookie. Try to squeeze the frosting as close to the thicker edge as possible without squeezing too much, so it won't spill over.

Yes! Powdered sugar, confectioners' sugar (including confectioners sugar and confectioner's sugar too), icing sugar, and 10X (a reference to the size of the particles) are all the same.

Royal icing is probably the most popular icing for decorating cookies. Made using egg whites or meringue powder, royal icing dries hard, making it a fabulous option for cookies you plan to package or mail. It's most often used for outlining and “flooding”, or filling in, cookie designs.