If you don't have a double boiler, use a metal bowl set over a pot of simmering water.
Martha Stewart Living
2 pounds white chocolate, chopped into 1/2-inch pieces
12 large candy canes
1/2 teaspoon peppermint oil
Line an 11-by-17-inch baking sheet with parchment, and set aside.
In the top of a double boiler, melt white chocolate, stirring constantly.
With a chef's knife or meat tenderizer, cut or pound candy canes into 1/4-inch pieces.
Stir pieces of candy canes and peppermint oil into the melted chocolate. Remove from heat, and pour the mixture onto the prepared baking sheet; spread evenly. Chill until firm, 25 to 30 minutes. Break into pieces, and serve. Store in an airtight container in the refrigerator for up to one week.