In a bowl, combine flour, cocoa, baking powder and salt with a whisk.
In a large bowl, beat butter, granulated sugar, and brown sugar with an electric mixer at medium speed, until light and fluffy
Beat in egg and vanilla until combined.
Add flour and cocoa mixture in three parts, beating to combine.
Stir in chocolate and cranberries.
Using a teaspoon, (a melon baller works great) roll dough into 1" balls, place on the prepared baking sheet, and flatten with your palm
Bake 10 minutes or until cookies are set. Allow the cookies to cool 2 minutes on baking pans before transferring to a wire rack to cool completely.
Notes
Dried cranberries can be substituted for fresh. Use ¾ cup dried cranberries.Make these cookies ahead and freeze. Cool cookies completely before pre-freezing them on their parchment lined baking sheets for an hour. Then put them in freezer bags and freeze for up to 2 months.