Millionaire Shortbread

FOR THE SHORTBREAD

1. Preheat the oven to 350 degrees Fahrenheit. Line an 8-inch square baking tin with baking paper.
2. Beat together ½ cup softened unsalted butter, and ¼ cup superfine sugar until light and creamy, scraping down the sides of the bowl as necessary.
3. Add 1 cup all-purpose flour, beating on low just until it starts forming small clumps. Scatter it into the prepared tin, then press it down lightly so there are no gaps. Bake for 25 minutes.

FOR THE CARAMEL FILLING

1. Combine 1 (14-ounce) can sweetened condensed milk, ½ cup packed brown sugar, and 3 ounces unsalted butter in a saucepan over medium-low heat. Stir for 6-7 minutes until the mixture is smooth and thickened slightly.
2. Stir in ½ teaspoon salt, then pour the caramel over the shortbread base.
3. Bake for another 20 minutes. Let it cool for 30-40 minutes at room temperature before transferring to the fridge.

FOR THE CHOCOLATE GANACHE

1. Once the caramel is cool to the touch, place 1 ½ cups finely chopped semi-sweet chocolate in a medium heat-proof bowl and set aside.
2. In a small saucepan, heat ⅓ cup heavy cream over low heat, swirling every so often, just until it starts to bubble.
3. Pour the cream over the chocolate and give the bowl a gentle shake to settle the chocolate under the cream. Leave for 1 minute to soften, then stir to combine. If it's not all melting together, give it a zap in the microwave for 20 seconds on half power, no more.
4. Pour the chocolate over the caramel and level out, then chill for at least 1-2 hours or overnight before cutting into squares.