Method
Preheat oven to 350 degrees F.
Evenly spray 1-1/2 to 2 qt soufflé dish or straight-sided casserole. Dust with crumbs. Set aside.
In covered jar or blender, shake or blend together milk, flour and salt, if desired, until smooth. Pour into medium saucepan, cook over medium-high heat, stirring constantly until mixture boils and is smooth and thickened. Stir in cheese if used, and seasoning, if desired, until cheese is melted. Set aside.
In large mixing bowl at high speed, beat egg whites with cream of tarter until stiff, but not dry, just until whites no longer slip when bowl is tilted. Stir egg yolks into reserved sauce until well blended. Stir in additional ingredients if desired. Gently, but thoroughly, fold yolk mixture into whites. Carefully pour into prepared dish.
For a "top hat", hold spoon upright and circle mixture to make ring about 1" from side of dish and 1" deep.
Bake until puffy, delicately browned and soufflé shakes when oven rack is moved gently back and forth, about 30 to 40 minutes.