Preheat oven to 375°F and line or grease 2 large baking sheets.

Melt 1.5 cups chocolate chips by transferring to a medium sized heat-proof bowl, set on top of a saucepan of simmering water until melted and smooth.

Whisk flour, cocoa powder, baking powder, espresso powder, and salt in medium bowl. In a large bowl, using a hand mixer, beat butter and sugars together until fluffy, and then add vanilla and peppermint extracts; beat until smooth. Add eggs, one at a time and beat until blended. Add in melted chocolate as well as the dry ingredients; slowly beating (or mixing by hand with a spatula) until just blended (don't over mix!). Add in remaining ½ cup chocolate chips and fold in gently.

Form 1-inch balls with dough and place on the cookie sheets about an inch apart.

Bake at 375 for 8 to 9 minutes, until set and cracked all over. Cool on baking sheet 5 minutes and then transfer to wire racks to cool completely.

Melt white chocolate (the same way as you melted the chocolate chips). Take off double boiler to cool for a couple of minutes. Place crushed candy canes into a small bowl. Dip each cookie in melted white chocolate so that half of the cookie is covered in white chocolate. Place dipped cookie on a cooled and clean cookie sheet, and sprinkle with crushed candy cane. Repeat with the remaining cookies.

Chill just until chocolate sets, about 20 minutes.