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Baking Tips

How to Get the Smoothest Frosting on Cakes

“Crumbing” separates homemade cakes from bakery-quality ones. Here’s how to do it. 

Published Dec. 19, 2023.

If you’ve made a cake at home, you know it can be a lot of hard work. Bake the layers (without having them stick), fill and stack the layers, and finally frost the cake.

And that’s where it usually falls apart.

Have you ever started to spread your frosting over the top, only to find your icing covered in cake crumbs?

Me too. Until I learned to first crumb the cake. I have baked and decorated a lot of layer cakes over the past 10 years, and my cakes have improved exponentially thanks to this one extra step.

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What Is Crumbing a Cake?

Crumbing a cake, also known as adding a crumb coat, is a decorating technique that professional bakers use to get supersmooth crumb-free frosting. 

All you do is spread a paper-thin layer of frosting on the cake, refrigerate the cake, and then proceed with decorating. This extra layer traps the cake crumbs, allowing your second layer of icing to shine, speck-free.

How to Crumb a Cake

Add this step into your cake-frosting process to make your homemade cake look bakery worthy. 

  1. Transfer about ⅓ of your buttercream, or whatever frosting you’re using, to a bowl. 
  2. Using a long offset spatula, cover the entirety of the cake, scraping any excess icing back into your bowl. 
  3. Continue to spread and scrape until your cake is fully coated and resembles a naked cake
  4. Transfer your cake to the fridge to let the crumb coat set, about 20 minutes. (The crumb coat should be firm to the touch.)
  5. Spread your remaining ⅔ buttercream on top of the crumb coat to give your cake the shiny, crumb-free coat it deserves.
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If your bowl of crumb-coat buttercream is full of crumbs, that’s OK! Keep using it. The quick trip to the fridge seals the crumbs to the cake like glue. 

Crumbs don’t bother you? By all means, skip the crumbing. It’ll still taste delicious! But if you want to really impress your friends with a bakery-worthy showstopper, give your cake a crumb coat.

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