Add room temperature butter to a mixing bowl with the brown and white sugar. Beat with an electric hand mixer until everything is creamed together nicely.
Add in baking soda, baking powder, and cocoa powder. Mix until well blended.
Then, beat in 2 eggs and peppermint extract. Beat until smooth.
Lastly, alternate adding the flour and milk in increments, beating the batter between each one (about 3-4 items alternating, adding ½ cup of flour at a time).
Fold in dark chocolate chips using a rubber spatula.
Pour the bread batter into a parchment lined or heavily greased loaf pan. Bake for 50-60 minutes or until a toothpick comes out clean from the center
Let the bread cool completely, frost with the icing, and top with crushed candy cane pieces. Slice and enjoy!