CHOCOLATE SOUFFLÉ

THE PERFECT SOUFFLÉ HAS A CRUSTY exterior, a dramatic rise above the rim, an airy but substantial outer layer, and a rich, loose center that is not completely set. A great chocolate soufflé must also convey strong, clear chocolate flavor.

A primary consideration when trying to create such a soufflé is the base, the mixture that gives substance and flavor to the soufflé as opposed to the lift and airiness provided by the beaten egg whites. In our testing, we found that egg yolks beaten with sugar are better than the classic Béchamel (butter, flour, and milk) or pastry cream (egg yolks beaten with sugar and then heated with milk). Without any milk, which can block out other flavors, the chocolate notes come through loud and clear.

The other key is the egg whites. We found that adding two more whites than yolks prevents the outside layer from becoming too cakey (a problem with most chocolate soufflés) and also gives better lift.

One factor we found to be of surprising importance was the baking dish. We tried using a standard casserole dish and the soufflé rosé right out of the dish and onto the oven floor. Whether using a single large soufflé dish or eight individual ramekins, the sides must be perfectly straight.

We also wanted to develop a soufflé base that could be prepared ahead of time and then baked as needed. Because beaten egg whites lose volume quickly, this is harder than it sounds. We tried refrigerating and freezing our basic soufflé batter and found that freezing portions in individual ramekins rather than a large dish worked best, although the rise was not as dramatic as we like. Adding confectioners' sugar to the beaten whites helped stabilize them and keep the rise high. We also added hot sugar syrup to the yolks to increase their volume, instead of plain sugar.

There are three ways to know when a chocolate soufflé is done—when you can smell the chocolate, when the soufflé stops rising, and when only the center jiggles when the dish is gently shaken.