Melt the milk chocolate in a double boiler or in the microwave in 30-second increments, stirring between each interval, until smooth. Pour the melted chocolate onto a Gefen Parchment-lined 9×13-inch (23×33-centimeter) pan and spread it evenly to form a thin layer. Let it cool and harden completely.

In a separate bowl, combine all the ingredients for the cookie dough layer.

Once the chocolate is completely cooled and hardened, press the cookie dough in an even layer over it. Place the pan in the freezer for 15 minutes to firm up the cookie dough layer.

Melt the bar of white chocolate. Pour the melted chocolate over the cookie dough layer and spread it evenly. Sprinkle with salt if you’d like. Let it harden in the freezer for about a half hour.

Once hardened, cut the bars into small squares or break them into haphazard pieces.