In a large bowl of a standup mixer, mix together the icing sugar, butter and peanut butter. Roll into 40 balls. Place on wax paper lined cookie sheets and set the sheets into the freezer for 30 min. or alternatively in the fridge. They will stay firmer in the freezer of course for dipping.
Melt the chocolate chips in a microwavable bowl at half power for 1 minute intervals, stirring until melted and smooth. Dip the balls in the chocolate laying them on a fork. Lightly bang off any excess chocolate on the side of the bowl. And place back on the cookie sheet. Add the sprinkles while the chocolate is stil wet. Store them in the fridge to set and then in an air tight container to keep. They will keep for 2-3 weeks in the fridge.
Nutrition calculation is an estimation only. If you need nutritional calculations for medical reasons, please use a source that you trust.