Preheat your oven to 350°F (175°C).
In a large bowl, mix the flour, cocoa powder, baking powder, and salt together.
In another bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy.
Add the egg and vanilla extract to the butter mixture, mixing until well combined.
Gradually add the dry ingredients to the wet mixture, mixing until just combined.
Scoop tablespoon-sized amounts of dough and roll them into balls, placing them on a lined baking sheet.
Bake in the preheated oven for 10-12 minutes, until the edges are firm but the centers are soft.
Let the cookies cool on the baking sheet for a few minutes before transferring them to wire racks.
Melt the chocolate melts in a microwave-safe bowl according to package instructions.
Once the cookies are cool, dip each one halfway into the melted chocolate and return them to the wire rack.
Before the chocolate hardens, add decorative candy eyes and red candies to create Rudolph's face.
Leave the chocolate to set completely before serving or storing.