Non-Alcoholic Margarita Punch

1 (12 fluid ounce) can frozen lemonade concentrate

1 (12 fluid ounce) can frozen limeade concentrate

1 cup confectioners sugar

4 egg whites

6 cups crushed ice

1 liter carbonated water

1 lime, sliced

coarse salt

In a 4 quart container, combine lemonade concentrate, limeade concentrate, powdered sugar, egg whites, and crushed ice; mix well. Cover and freeze at least 30 minutes before serving.

Spoon 2 cups slush mixture into blender. Add 1 cup of carbonated water. Blend until frothy. To serve rub rim of glass with lime slice, dip in salt, and fill glass. garnish with lime slices.