Velvety Cocoa Frosting

Ingredients
- 3 c confectioners sugar
- 12 to 34 c cocoa
- 12 c butter softened
- 14 c water
- 1 egg yolk
- 1 tsp vanilla
Directions
- In large bowl with mixer at low speed beat confectioners sugar cocoa butter water vanilla and egg yolk until smooth occasionally scraping bowl with rubber spatula