Royal icing is made with confectioners sugar, egg whites and lemon juice. Make royal icing to make fireworks with tips from a professional baker in this free holiday recipe video about making a Fourth of July cake. Expert: Karen Weisman Bio: Karen Weisman graduated from Boston University with a degree in Hotel and Food Management. Since then, she has helped a national grocery store chain develop and launch a gourmet food division. Filmmaker: Karen Weisman