Preheat oven to 350°F.
In a large bowl, cream the butter and sugar and then add the egg and vanilla. Mix well.
Add the flour, sifted cocoa, baking soda and baking powder together. Sift as needed.
Add the flour mixture to the sugar mixture and stir. (Can also use a hand held mixer) It will be a dry mixture.
Scoop out the dough onto a parchment lined baking sheet. Cookies will spread, so be sure to place them at least 2 inches apart. (I used a measuring scoop that holds about 2 1/2 tablespoons of batter.)
Place some sugar in a small bowl or plate and dip the bottom of a glass into the sugar and press the cookie down. (I sprayed the glass with non-stick spray the first time, you only need to spray it once.)
Bake 8-10 minutes or until tops are just dry. Let cool on pan for a few minutes so that you can move them to a cooling rack without breaking them.