Melt chocolate over low heat in a small saucepan. Meanwhile, beat butter with an electric mixer. Add sugar; beat again. Pour in melted chocolate. Add eggs, vanilla, and mint. Beat the chocolate mixture into the butter/sugar mixture. Add flour, baking powder, and salt. Combine with a spoon. Wrap cookie dough and place in the fridge for about half an hour.

Preheat oven to 350-degrees. Shape dough into 1-inch balls. Roll in powdered sugar and place about two inches apart on a lightly greased cookie sheet. Bake at 350-degrees for approximately 10 minutes, until tops are cracked.