Soufflés Can Absolutely Be Made Ahead Of Time. Here's What To Do
Many are under the impression that the notoriously difficult dish, the soufflé, must be baked almost immediately after the whipped egg whites are combined with the yolk and flour mixture. And the logic behind this is sound, as whipped ingredients usually lose their tight air bubbles as time passes. However, it is possible to prepare them ahead of time as long as you store your soufflé properly in the refrigerator or freezer. In fact, chefs have been making soufflé batter and popping it in the oven in time for the dinner or brunch rush for years.
To prepare soufflés in advance, follow your soufflé recipe as you would normally. This usually begins with making the custardy part with some variation of egg yolks, an addition like chocolate or lemon or cheese, butter, and a bit of flour or cornstarch. This component is sometimes done over heat so the ingredients melt together and become thicker. Then, egg whites are whipped to create much of the volume of the soufflé. The main concern with storing soufflé batter may be to maintain those airy egg whites, but when you mix them into the batter, they actually hold onto their structure longer than you'd imagine.
The exception to the rule
You can prepare the batter hours, or even a day ahead without having to worry about ruining the flavor and airy texture. But this doesn't mean you can prepare every soufflé the same way. A classic dessert soufflé or cheese soufflé will taste just as good when you make them in advance, but some others will need a few adjustments to the process.
If you're making a soufflé with vegetables or meats, hold off on adding them to the batter at this step as they will release liquid as they sit. You can finish off the soufflé batter and pour them into the same ramekins you'll bake them in. Cover the top with plastic wrap and keep them in the refrigerator for up to 24 hours. You could even freeze the soufflés for about a week. If you're freezing them, defrost them in the microwave for about 40 seconds before popping them in the oven. When dinner time comes, you can take those soufflés out of the fridge and cook them. Or, for vegetable soufflés, gently fold the vegetables into each ramekin before cooking.