Line a large baking sheet with parchment paper and set aside.
Set up two double broilers, and warm up. Place all of the semi sweet chocolate in one of the double broilers, and all of the white chocolate in the other double broiler. Slowly and gently melt the chocolate, stirring regularly.
Once all of the chocolate is melted. Remove from heat. If using the optional crème de menth flavoring, add it to the white chocolate only, and stir well to combine.
On your parchment lined baking sheet, pour all of the semi sweet chocolate on first. Using an offset icing spatula, or regular spatula, spread the semi sweet chocolate out into an even layer that covers the entire pan.
Next pour the white chocolate on top. Very gently and carefully spread the white chocolate over top. You don’t want the chocolate to swirl quiet yet, be sure to get an even layer, covering the entire pan.
Now time for the swirl! Grab a regular spoon and holding the spoon vertically begin to swirl and twist the spoon. Once you are happy with the swirl, gently tap the pan against the counter a few times to help the chocolate flatten.
Sprinkle all of the crushed candy canes on top. Place in the refrigerator and let set for at least 2 hours or more.
When chocolate is set, remove from the refrigerator. Carefully break chocolate apart with a knife into pieces.