Combine marshmallows and milk in top of double boiler; bring water to a boil. reduce heat to low, cook until marshmallows melt; stirring frequently. remove from heat; cool, stirring occasionally. Add creme de menthe and creme de cacao; fold in whipped cream.Spread ice cream evenly in crust and pur marshmallow mixture over ice cream. Freeze at least 6 hours. Garnish with whipped cream.