Sherbet In The Half Shell
["4 grapefruits", "1 1/4 c. sugar", "1/3 c. water", "3 egg whites", "1/4 tsp. cream of tartar", "dash of salt", "fresh mint leaves or maraschino cherries (for garnish)"]
["Halve and juice grapefruits.", "Measure 3 cups juice and pulp; set aside.", "Pull out and discard membrane from shells; freeze shells.", "Combine sugar and water in small saucepan; bring to boil, stirring until sugar dissolves.", "Cook to soft ball stage, 238\u00b0 on candy thermometer."]
["grapefruits", "sugar", "water", "egg whites", "cream of tartar", "salt", "mint"]