The method for making almost all main-course soufflés is approximately the same, and anyone who learns the technique can vary the soufflé at will. The basis for these soufflés is a simple white sauce to which a solid of some sort is added. The solid may be a seafood (such as flaked crab or chopped shrimp) or a cheese or, as in one of the recipes that follows, mushrooms. To this egg yolks are added. They are cooked briefly without boiling. These eggs yolks, as always, tend to thicken a sauce. Remember, too much heat may curdle the yolks.
The thing that makes a soufflé puff are the beaten egg whites that are folded in. When these whites are exposed to the oven heat, the globules expand and give the soufflé its gossamer texture. The easiest most sure-fire way to add the whites is this: stir in half the whites until they are well incorporated in the sauce, then gently fold in the remaining whites with a rubber spatula. Make sure the spatula cuts down into the mixture, scrapes down to the bottom then up again. The whites must not be folded in too thoroughly. If a few specks of white still show, that is all right too.
To make a soufflé, use a straight-sided soufflé dish. The interior of the dish—bottom and sides—should be buttered so the soufflé can slip up the sides as it bakes.
There are no great mysteries involved in the making of soufflés. Actually, they are quite easy to make if a few simple directions are followed. There are many ways to make soufflés and almost no two cookbooks will duplicate the process. I have personally found the following things to result in a perfect soufflé:
There is much discussion as to whether soufflé dishes should be buttered before using. They should be and they should also be chilled in the refrigerator or briefly in the freezer before the soufflé mixture is added.
The basic mixture for a soufflé is a simple white sauce. However, less butter should be used than normally in making the sauce. For a perfect soufflé, the sauce should be unusually thick. This is achieved by making the sauce with lots of flour in relation to the amount of milk. A little more thickening with cornstarch helps. The sauce is further thickened with egg yolks. And here is a point that few recipes make. The sauce, after the yolks are added, must be cooked ever so briefly. After the yolks are added, the sauce is brought to a boil only for seconds, and at this point the sauce must be stirred rapidly, preferably with a wire whisk.
The egg whites must be beaten until stiff and stand in peaks. Half the whites are whisked into the sauce. The remainder are carefully folded in with a rubber spatula. The mixture is now ready to pour into the prepared dish.
The soufflé must be cooked in a preheated oven. The oven temperature may range from about 350 degrees to 400 degrees and the temperature will, naturally, affect the cooking time. The higher the temperature, the more rapidly the soufflé will cook.
A classic soufflé is light, delicate, and quite moist in the center when it is done. Some people, however, prefer a firmer center (and therefore cook the soufflé longer).
As to the size of the soufflé dish, it may be large or small. The important thing is to have it completely filled with the soufflé mixture before baking. The best soufflé dishes are white ceramic rather than metal.