Velvety Cocoa Frosting - cooking recipe

Ingredients

3 c. confectioners sugar
1/2 to 3/4 c. cocoa
1/2 c. butter, softened
1/4 c. water
1 egg yolk
1 tsp. vanilla

Preparation

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.