Combine mayonnaise and flour, mix well. Gradually add milk; cook stirring
constantly over low heat until thickened. Add salt and cheese, continue
cooking until cheese melts. Cool slightly; stir in broccoli and slightly
beaten egg yolks. Fold in stiffly beaten egg whites; pour mixture into
1-1/2 quart casserole. With tip of spoon, make slight indention around
top of souffle to form a top hat. Bake at 300 degrees for 10 hour and 15
minutes. Serve immediately.
Variation: add 3/4 cup finely chopped ham and omit salt.