A smooth buttercream finish can elevate a simple cake into a polished, bakery-worthy dessert. However, achieving clean sides is a common hurdle for beginner cake decorators.
Fortunately, smooth buttercream doesn’t require perfect technique from the start. Once you learn the proper steps and put a little extra effort into the process, you’ll be able to get a much cleaner finish.
Cool Your Cake Layers First
Make sure your cake layers are cool before you start decorating. If your cake is still warm, the buttercream will melt, making it harder to decorate.
Trim any uneven cake layers so they’re stacked properly. You want a solid base before you decorate.
Start With a Crumb Coat
A crumb coat is a thin layer of buttercream that covers the cake before the final layer of frosting. The main purpose of a crumb coat is to seal in crumbs so they don’t show through the finished frosting.
Make It Thin
It’s okay if your crumb coat isn’t perfect. Apply a thin layer of frosting and smooth it out, then refrigerate the cake until the frosting firms up. This will give you a clean canvas for the final layer.
Use Plenty of Frosting
Don’t be afraid to add plenty of buttercream to your cake when applying the final layer. Making clean sides with a very thin layer of frosting is incredibly difficult.
Spread a thick layer of frosting around the sides and top of the cake. You can scrape off excess later.
More Can Be Better
I know this sounds counterintuitive, but having more buttercream allows you to get smoother sides. You’ll be able to use a scraper to remove the excess, which reveals a smooth surface underneath.
Use a Cake Scraper
A cake scraper is a must-have tool when you’re smoothing buttercream on your cake.
Hold the scraper firmly against the side of the cake and slowly rotate the cake stand. Avoid moving the scraper up and down while rotating. Instead, try to remove a small amount of excess buttercream with each pass.
Remove Excess From the Top Edge
After you’ve smoothed the sides, you’ll need to remove excess frosting from the top edge.
Using your scraper or spatula, pull the frosting towards the center of the cake. Repeat this all the way around the cake until the top edge is clean.
Don’t Obsess Over Clean Sides on the First Pass
If there are gaps or uneven areas, just add a bit more buttercream and smooth it again.
Most cakes require multiple passes to get the sides nice and clean. Achieving a professional-looking finish often takes multiple attempts.
Chill When Needed
If your buttercream gets too soft, or the cake begins to move around while you’re decorating, pop it in the fridge for a few minutes. A firmer cake is much easier to scrape and smooth.
But avoid letting your cake alternate between freezing and room temperature. Wait for your buttercream to soften a bit before you continue working.
Keep Practicing
Expect your first couple of cakes to have uneven sides, rough edges, or imperfections here and there. That’s fine.
The more you practice, the better you’ll become at using the right amount of frosting, holding your scraper correctly, and knowing how fast you should rotate the cake.
Wrapping Up
Getting smooth buttercream takes practice. Begin by chilling your cake, adding a crumb coat, and then adding plenty of final layer frosting. Use a scraper to remove the excess, and keep refining your technique.
There’s no need to worry about perfecting your technique to get a great-looking cake. Focus on controlling your scraper, making minor adjustments, and practicing regularly. Before long, your cakes will have much cleaner sides.
