Fixing Broken Custard
If a custard gets overheated and becomes lumpy, is it a lost cause? Or can it be salvaged?
When custards such as crème anglaise are heated, they turn thick and creamy as milk and egg proteins unfurl and bond with each other. However, if they are overheated, too many bonds form and the proteins clump.
To find a fix for lumps, we overcooked a simple custard to 205 degrees (the recommended temperature is 175 to 180 degrees), at which point it was full of large lumps. Rescuing the custard turned out to be a cinch with an immersion blender. A quick buzz effectively broke down the clumps, restoring a perfectly creamy texture (which didn’t break when we refrigerated the fixed custard).
If you notice lumps beginning to form in a custard, immediately pour it out of the hot pot into a bowl and pulse it with a handheld blender in five-second intervals until it is nearly smooth. This can take from 15 to 45 seconds, depending on how big the lumps are. Be careful not to overprocess or you can wind up with irreparably thin, watery custard. Don’t use a blender or food processor; they incorporate too much air and will leave the mixture frothy, not creamy. After blending, pour the liquid through a fine-mesh strainer to remove any remaining lumps and continue with your recipe.
SMOOTHED OVER: Pulsing with an immersion blender restores smoothness to lumpy custard.