Preheat oven to 350ºF. In a bowl combine flour, cocoa powder, baking soda, baking powder and salt; set aside.
In a mixing bowl, beat butter and sugar with electric mixer on medium-high for one minute. Beat in egg and vanilla for 2 minutes. Gradually mix in dry ingredients over 3 additions.
Shape into 1-inch balls. Roll in sugar. Place 2 inches apart on a parchment-lined baking sheet. Press your thumb into the centre of each ball to make a well. Place a cherry (or half cherry) in the well. Bake for 10-12 minutes until the edges are firm. Transfer to rack to fully cool.