Line two baking trays with greaseproof paper. Put the peppermint candy canes in a bag and crush them up in bag.
Break up the chocolate and gently melt it along with the butter and the peppermint extract in a bowl set over a pan of simmering water, stirring occasionally.
Once all the chocolate and butter is melted then take off the heat and stir in the condensed milk until fully incorporated.
Mix in the flour, white chocolate chips and peppermint candy canes then scoop them onto the trays and refrigerate the cookies for about 10 minutes.
Pre-heat the oven to 180 degrees Fan 160 degrees Gas 4. Place the trays in the oven and bake for about 15 minutes.
Once baked, leave to cool for a few minutes on the tray then transfer to a wire rack until fully cooled.