In a large bowl, stir the cocoa and molasses into the warm butter. In medium bowl combine flour, baking soda, salt, cinnamon and cayenne pepper. Add sugar, egg and vanilla extract to the large bowl. Stir dry ingredients into the wet. Cover and chill dough for as little as an hour or up to 3 days.,

When ready to bake, preheat oven to 350 degrees. Roll 1 tablespoon of dough into balls (a #50 cookie scoop is great for this), and roll them in the remaining white sugar. Place cookies 2 inches apart onto ungreased baking sheets.,

Bake cookies, one sheet at a time, for 10-12 minutes, until cookies are puffed, centers are set and they are beginning to form cracks. Do not overbake. Leave on sheets until they are cool enough to transfer to a wire rack and let cool completely.,

If you want a slightly more substantial cookie, use a #30 cookie scoop, 2 tablespoons dough, for each cookie. You will need to add a minute or two to the bake time and the batch will make about 18 cookies instead of