Line a 10 x 15 inch cookie sheet with aluminum foil. Smooth out any wrinkles in the foil then set aside.
Melt dark chocolate using a double boiler over simmering water then stir in 3/4 teaspoon of peppermint schnapps.
Spread melted chocolate onto prepared cookie sheet. Note: layer will be very thin.
Melt white chocolate with double boiler over simmering water then stir in remaining 3/4 teaspoon of peppermint schnapps.
Using a spoon, drop white chocolate by dollops over dark chocolate then swirl the two together with a butter knife.
Sprinkle top with crushed candy canes then refrigerate for 1 hour until set.
Remove foil from bottom then break bark into serving-sized pieces.
Store bark in an airtight container in the refrigerator up to 2 weeks.