In a small bowl, beat egg whites and salt until soft peaks form. Gradually add sugar, 1 tablespoons at a time, and continue beating until stiff and glossy.
Place cake slices on ungreased baking sheet,. Top each with ice cream and quickly cover with meringue, being sure to seal edges completely. Swirl meringue into peaks. Keep in freezer until ready to bake. Freeze for at least 1 hour. (To store for longer periods, up to 2 weeks, place unbaked Alaska in cake box and over wrap with plastic).
Preheat oven to 475°F Bake 2-4 minutes or until meringue is delicately browned. Serve at once.
Choose ice cream that contrasts in color and flavor with cake, i.e. vanilla ice cream on brownies; peppermint on chocolate cake; fruit sherbet on jelly roll.