Mix flour, natural unsweetened cocoa, baking soda and salt in a medium bowl.
In a large mixing bowl, using high speed of an electric mixer, beat butter for 30 seconds or until slightly softened. Add both sugars and beat until creamy; beat in honey and vanilla extract. Add egg and beat just until mixed. Using a mixing spoon, stir in the flour mixture, being careful not to over-beat . Stir in chopped hazelnut flavored chocolate bars. Cover dough and chill for an hour.
Preheat oven to 375 degrees F. Have ready two shiny, ungreased cookie sheets or sheets lined with foil.
Form chilled dough into balls about 1 1/4 inch. Dip tops in a tiny bit of sparkly sugar if desired. Place dough balls approximately 2 ½ inches apart on cookie sheets and bake one sheet at a time on center rack of oven for 10 minutes or until cookies appear puffed and set – do not over bake. Let cookies cool for 3 minutes on cookie sheet then transfer cookies to a wire rack to cool completely