Step 1

In a large mixing bowl, beat butter and granulated sugar together. Beat in eggs, one at a time. Add flour and cocoa powder. Fold in chopped chocolate bars.

Step 2

Refrigerate one hour.

Step 3

Shape into ball (large tablespoons), and roll in powdered sugar, covering completely.

Step 4

Drop on parchment paper lined cookie sheet and bake in a 350 degree oven for 10-12 minutes. Allow to cool on pan 10 minutes before removing to wire rack.