Trick to Fix Broken Buttercream Frosting
It may look like fluff, but buttercream frosting is a gentle emulsion. When low temperatures upset this delicate balance, the buttercream can break down. “Break” can refer to the state of the emulsion, or to your heart, because the sight of broken buttercream is, oh, so sad (and disgusting). Luckily, fixing a broken buttercream is very easy.
Buttercream most often breaks during initial mixing or when reheating frosting that you have stored in the refrigerator or freezer. When it happens, you will know. At best, it will look loose, greasy, or watery. Some call it a “split”. At worst, there will be hundreds of white chunks floating around in a clear, syrupy liquid. This happens most often with marshmallow meringue buttercream, making it completely non-marshmallow. It’s not beautiful. Buttercream is not fully emulsified, and barring a recipe error, buttercream is your problem and solution.
You need to heat this oil along with the rest of the mixture. Those of us who deliriously reached out to poke broken buttercream felt that the white lumps were hard, maybe even hard. This indicates that the fats have cooled and separated from the rest of the mixture. To get a soft, spreadable frosting, your main ingredient must be soft and spreadable. This means warm oil. It can be an “I told you so” moment for the room temperature ingredients team, but buttercream can go bad even if you started with softened butter. Forgive yourself. This is easy to fix. You just need to bring the frosting up to temperature. The following methods can fix stubborn frosting that refuses to emulsify and quickly reheat frosting you’ve kept in the refrigerator to a paste-like consistency.
use the flame
The most fun way to heat up frosting is with a blowtorch. This only works if your mixer has a metal bowl. Don’t do this with glassware. Turn on the mixer with the broken icing and run the burner flame along the bottom and sides of the bowl as it mixes. Stop every 10-20 seconds or so (depending on the size and power of your flashlight, this may be less time). The mixture against the metal will melt. Let the hot mix and it will begin to heat the rest of the mixture to the right temperature. The broken globules of fat will become smaller and larger until they turn into a single homogeneous mixture. Alternatively, you can take a metal bowl and hold it over a gas burner flame for a few seconds to melt some of the mixture. Return it to the mixer to blend.
Melt some in the microwave
Not everyone has a flashlight in the kitchen, but chances are good that you have a microwave. Remove about a cup of the broken frosting and place it in a microwave-safe measuring cup. Heat the icing in the microwave until it melts, it won’t take long, 15-20 seconds. Pour the hot, melted frosting back into the rest of the mixture and stir until fluffy. This can be repeated if necessary.
Mix and wait
Although it may take a while, you can turn on the mixer and leave. No flame required. Set the mixer speed to high or medium, but I usually use the highest speed that the frosting can handle without flying out of the bowl. (At lower speeds, it will take a little longer to warm up.) The butter will eventually reach room temperature no matter what, and a mixer will help speed that up. The caveat is that emulsification will not occur if the ambient temperature is below 65°F ( the lowest temperature for softened butter ). If the weather is cold, try one of the other two methods and you’ll be ready to freeze your cake in no time.