Preheat oven 375° F.
Cream butter, sugars, vanilla extract and cocoa powder. Stir in remaining ingredients and blend well. Refrigerate 30 minutes.
Drop dough by rounded tsp onto ungreased cookie sheet about 2 inches apart. Bake until cookies are set, 5 to 8 minutes. Cool slightly and remove from pan.
When making large cookies, press down slightly on cookie dough to help cook more evenly. Bake slightly longer, 8 to 10 minutes.Makes 4 Source: