Millionaire's Shortbread

Prepare the crust: Preheat oven to 375°F (190°C). Lightly grease and flour a 9-inch square baking pan. (5 minutes)

Make the shortbread: In a large bowl, whisk together the flour and brown sugar. Cut in the cold butter using a pastry blender or your fingertips until the mixture resembles coarse crumbs. (10 minutes)

Press and bake: Press the mixture evenly into the prepared pan. Prick the surface all over with a fork to prevent puffing. (5 minutes)

Bake the shortbread: Bake in the preheated oven for 18-20 minutes, or until lightly golden brown. Let cool completely in the pan. (20 minutes)

Craft the caramel: In a medium, heavy-bottomed saucepan, combine the sweetened condensed milk, butter, and brown sugar. (2 minutes)

Cook the caramel: Cook over medium-low heat, stirring constantly with a heat-resistant spatula, until the mixture comes to a gentle boil. Reduce heat to low and continue cooking, stirring constantly, until the caramel is thickened and a deep golden brown color, about 8-10 minutes. It should be pulling away from the sides of the pan. (10 minutes)

Assemble the layers: Pour the hot caramel evenly over the cooled shortbread crust. Refrigerate for at least 1 hour, or until the caramel is firm to the touch. (60 minutes)

Craft the ganache: Place the chopped milk chocolate in a heatproof bowl set over a saucepan of simmering water (double boiler). Ensure the bottom of the bowl does not touch the water. (2 minutes)

Melt the chocolate: Stir the chocolate frequently until it is completely melted and smooth. Remove from heat. (5 minutes)

Finish and chill: Pour the melted chocolate evenly over the chilled caramel layer. Refrigerate for another 15-20 minutes, or until the chocolate is set. (20 minutes)

Slice and serve: Once fully chilled, lift the shortbread from the pan using the edges of the parchment paper. Cut into squares or bars with a sharp knife. For clean cuts, run the knife under hot water and wipe dry between each cut.