Royal Icing:

(Yield 8 lbs). Sift sugar with cream of tartar Using stand up mixer with paddle attachment, add 6 lb of sugar, holding 1 lb in reserve On first speed, add the lemon juice and egg whites, mixing to incorporate, add a little of the reserved sugar if needed. On second speed, trying not to incorporate air into the mixture, mix to stiff peak. While using, keep container covered with a wet (not dripping) cloth. When storing, use a wet cloth with a tight container cover.