Line shallow baking pan with parchment paper; set aside. Place wafers and cocoa mix in food processor bowl; pulse wafers into fine crumbs. Add pudding and Reddi-wip; pulse until mixture comes together and forms a ball. Add marshmallows; pulse until marshmallows are cut into small pieces.
Roll wafer mixture into 1-inch balls; place on pan. Freeze 30 minutes or until set.
Place morsels and oil in small microwave-safe bowl. Microwave on HIGH 30 seconds; stir. Microwave on HIGH 30 seconds more or until softened; stir until mixture is melted completely. Roll a truffle in mixture until evenly coated. Remove with fork, letting excess drip off. Place on pan. Immediately sprinkle with some colored sugar, if desired. Repeat with remaining truffles. Refrigerate 1 hour or until firm. Store in airtight container in refrigerator.