1. Place applesauce in bowl; stir in lemon rind and nutmeg. Beat egg whites in small bowl until frothy; add cream of tartar and beat until whites hold peaks.
2. Slowly add brown sugar while continuing to beat until stiff peaks form and whites are shiny. Stir 1/3 egg whites into applesauce mixture to lighten. Fold in remainder egg whites gently.
3. Refrigerate, covered, until ready to serve. Serve with an additional sprinkle of nutmeg if desired.