Cake 911: Help, my cake is bulging!
We've all heard the phrase "Crumb Coat & Chill" (made famous by Yolanda of How To Cake It).... However, what do you do when you crumb coat, chill and ice your cake for a second time only to have it bulge? Super-frustrating, right? I know your pain! This photo was recently shared by one of my amazingly talented students after she reached out for help to fix the bulge at the base of her cake. She also was working on a fondant cake that was experiencing the same issue. While correcting a bulge (or two) is quite simple under fondant, dealing with bulges under buttercream are a little more complicated. Ask yourself the following questions:
1. What kind of "icing" am I using?
I could tell by looking at this photo that my student was using a "crusting" buttercream to ice her cake, and this was indeed the case. This type of icing typically contains shortening (instead of butter) and a lot of powdered sugar. Left to stand, this icing develops a crust that can further be smoothed with parchment paper or a fine textured paper towel.
If you are planning to crumb coat your cake, I would NOT recommend icing your cake with a crusting buttercream where shortening has been used instead of butter. I would highly recommend icing with Swiss meringue buttercream (SMBC) or ganache instead. Why? Swiss meringue buttercream contains butter and will set sturdier than a crusting buttercream when chilled in the refrigerator. Ganache (made from chocolate and heavy cream) doesn't require refrigeration at all to set. If you have time, you can leave a cake iced in ganache at room temperature to set for a few hours. If you're running low on time, the refrigerator (set to cool, and not cold; See question 3) will help the ganache set faster.
2. Did I make my crumb coat thin enough?
You should always be able to see your cake through your crumb coat. If your crumb coat is too thick, it may fail and pull your final coat of icing away from your cake.
3. Did I really chill my cake or is it too cold?
There is a fine line between chilling your cake and making it cold. Chilling your cake for 5-10 minutes after applying the crumb coat is fine... Refrigerating your cake for 30+ minutes after applying the crumb coat is a no-no! Taking a cake directly from the refrigerator and working with it immediately is a recipe for disaster.
When a cake leaves the refrigerator, it releases air as it works to acclimate to being at room temperature. The air can become trapped under icing and fondant and create air pockets that translate to bulges on any surface of the cake. If you're concerned that your cake is too cold, allow it to sit at room temperature for 10-15 minutes before adding the final coat of icing or fondant.
Helpful Tip: To help your cake release air as it chills, consider lightly weighting it down by placing a clean, dry grease-proof cake board over the top and sitting a medium-weight can or jar on top of the board.
4. It's too late, and now I have bulges on my cake... What do I do now?
If you've iced your cake with crusting buttercream or SMBC, remove all of the icing and start over following the tips above if possible. If you're running low on icing, only remove the icing at your bulge and re-ice that section.
If you're covering your cake with fondant, use a straight pin to pierce the fondant at each air pocket. Apply light pressure with your hand to release the air and use a fondant smoother to gently push the fondant back into place.
I told you it was much easier to fix with fondant!
P.S. Looking to avoid more cake-related mistakes? Check out this video, and subscribe to my YouTube channel for more cake decorating tips and tutorials