[header] How to make royal icing [title] Gather your ingredients. [step] Here's what you'll need to make about four cups of royal icing with egg whites : [substeps] 3 cups (700 ml) powdered sugar, plus additional as necessary 2 egg whites 1 tsp (5 ml) lemon juice [title] Sift the powdered sugar into a bowl. [step] Sifting is not necessary but will help keep your icing from getting lumpy. 
[title] Separate the egg whites into a separate bowl. [step] Crack an egg and then turn it crack-side up.