Choose the icing type: buttercream, royal icing, cream cheese, glaze, or fondant
Prepare ingredients and equipment:
Sift powdered sugar (if using)
Soft butter (for buttercream) or room-temperature ingredients (for cream cheese)
Mixing bowls, whisk/hand mixer, rubber spatula
Food coloring and flavoring (optional)
Buttercream (simple):
Cream softened butter until smooth
Gradually add powdered sugar, mixing until thick and fluffy
Add milk or heavy cream one tablespoon at a time to reach desired consistency
Add vanilla (or other flavoring) and pinch of salt
Adjust thickness with more sugar (thicker) or more milk (thinner)
Buttercream (American, for piping):
Use more powdered sugar for firmer consistency
Add less liquid until the icing holds peaks
Royal icing:
Combine powdered sugar and meringue powder (or use egg whites) in a bowl
Add water a little at a time while mixing until smooth
Mix to stiff peaks for piping or to ribbon stage for flooding
Cover icing to prevent drying; adjust with water for thinner consistency
Royal icing flooding consistency:
Stir until it ribbons and settles within about 10 seconds
Add water dropwise to thin; add sugar to thicken
Cream cheese icing:
Beat softened cream cheese until smooth
Add butter and beat until creamy
Gradually add powdered sugar and mix until smooth
Add vanilla and a small splash of milk if needed
Glaze (quick pourable icing):
Whisk powdered sugar with a small amount of milk or lemon juice
Add liquid gradually until pourable
Stir until smooth; strain if needed
Fondant-style icing (rolled or spread):
Knead softened fondant until pliable
Roll or press onto a prepared surface
Smooth with a fondant smoother or hands (lightly dusted with sugar)
Flavoring and color:
Add vanilla, almond, lemon, or cocoa gradually
Add gel food coloring in small amounts; mix thoroughly
Consistency checks:
For spreading: thick but smooth, slowly settles
For piping: holds shape and peaks
For flooding: ribbons and levels out
Apply icing:
Cool cake completely before icing
Crumb coat if desired, then chill briefly
Spread or pipe using an offset spatula or piping bag
Smooth with a bench scraper or spatula
Storage:
Refrigerate buttercream/cream cheese cakes (covered) if needed
Let refrigerated cakes sit briefly at room temperature before serving
Keep royal icing covered to prevent crusting