Everyone knows that biscotti means twice-baked and that mandelbrodt—essentially Jewish biscotti, if not the other way round—also gets its appealing, bone-dry crunch from a double bake. But why stop there?
Experimenting with shortbread years ago, I found that the centers of my thick shortbread pieces often remained slightly doughy—rather than dry-but-melt-in-your-mouth tender. When I published the recipe, I added troubleshooting advice, instructing the cook to put shortbread pieces back in the oven if they weren’t completely crunchy. I later realized that the twice-baked pieces were always better than the others. From then on, the double bake became a part of both the recipe and its title. Twice-Baked Shortbread (from Chewy Gooey Crispy Crunchy Melt-in-your-Mouth Cookies) was thus born! I swear by it still.
Now, whenever any batch of cookies or crackers turns out chewy or bendable, when they ought to be snappy, I put them right back into the oven. And you should too.
Here’s what you need to know about double baking. First, avoid jumping the gun. Never judge the texture of a cookie or cracker while it’s still hot: These items usually crisp up—if they are going to—after they are completely cool. The same is true when you’ve twice-baked them: evaluate only after they are cool. (No one knows how hard it is to wait before tasting more than I do.) Once it’s clear that you do have limp cookies or less-than-crispy crackers, put them back into a preheated 300° F or 325° F oven, regardless of the original (presumably higher) baking temperature. I tend to use 300° F for items that can’t afford to get darker, and 325° if a little extra color won’t hurt. The idea is to reheat and let the items stay hot for a few minutes to drive out extra moisture—not necessarily to make them browner or darker (unless they were too pale to begin with). At these low-ish temperatures, you are also less likely to over bake or burn your treats. Generally, the second bake requires only 10-15 minutes—the first 5 of which are merely reheating the items.
Once cookies or crackers are cooled and crispy or crunchy, store them in an airtight container to keep them that way.