Why rest crepe batter?
In reading a bunch of crepe recipes in preparation for the crepe cake, one common element stuck out to me: they all called for resting the batter before cooking. Times varied from an hour to overnight, and none of them offered an explanation. I like being able to justify every step in a recipe beyond, well, Dorie Greenspan told me to do it, so I decided to do a little experiment.
I made a double batch of crepe batter using my recipe from the cake. I cooked off some crepes immediately, more after 2 hours, and the rest after 10 hours. The verdict? First of all, crepes are delicious and I should make them more often. More to the point, I could definitely taste a difference in the rested batter. The crepes I cooked right away did not spread evenly in the pan, leading to unappealingly thick crepes. Once the batter rested, especially overnight, it became easier to work with and created thinner, more even crepes. The rested batter also made less chewy, more tender crepes.
Let’s take a look at three things going on in the batter during that rest that will affect the final crepe. First, sitting in the fridge gives any gluten developed during mixing some time to relax and unwind. Mixing will inevitably cause some gluten formation, which pulls proteins together for more structure, but we want a soft, tender crepe. Letting the batter sit will loosen the gluten web. Second, the starch in the flour absorbs more water until it becomes fully hydrated. This is especially important for buckwheat crepes and their potential grittiness from still-thirsty starch, but it lifts our white flour crepe to greater heights of smoothness as well. Finally, giving the batter a break means that any air bubbles introduced by mixing have time to work their way to the top of the bowl and escape instead of hanging out in the batter and expanding as you cook. These bubbles work great for pancakes but cause unwanted lift in your crepes.
So science and observation both say give it a rest and let the batter sit overnight. It’ll help, plus making the batter the night before means less work in the morning. But if it’s just not going to happen, don’t let the needy gluten and its required naptime get in between you and some fresh crepes. Douse them in honey and sugar, fill them with cream cheese and raspberry jam, or just throw in an obscene amount of chocolate–they will still be delicious.