Ingredients:
1 1⁄2 cups all-purpose flour, plus more for dusting
12 tbsp unsalted butter, softened,
plus extra for greasing
1⁄2 cup sugar

For the caramel filling:
4 tbsp unsalted butter
1⁄4 cup light brown sugar
14oz (400g) can condensed milk
For the chocolate topping
7oz (200g) milk chocolate
2 tbsp unsalted butter
2oz (50g) dark chocolate

Method:
Preheat the oven to 325°F (160°C).

Put the flour, butter, and sugar in a bowl and rub together to make crumbs. Grease the pan and dust with flour. Put the mixture into the pan and press it down with your hands until it is compact and even.

Bake in the center of the oven for 35–40 minutes, until light golden brown. Leave to cool in the pan.

For the caramel, melt the butter and sugar in a heavy-bottomed saucepan over medium heat. Add the milk and bring to a boil, stirring constantly.

Reduce the heat and cook on a steady simmer, still stirring constantly, for 5 minutes, until it thickens and darkens to a light caramel color.

Pour the caramel over the cooled shortbread and leave to cool.

For the chocolate topping, put the milk chocolate and butter in a heatproof bowl over a pan of simmering water, without touching the water, until just melted. Stir well.

Melt the dark chocolate without butter in a separate bowl in a similar way.

Pour the milk chocolate over the set caramel and smooth out. Pour the dark chocolate over the surface in a zigzag pattern and drag a fine skewer through the 2 chocolates to create a marbled effect.

Leave to cool and harden before cutting into squares. STORE These will keep in an airtight container for 5 days.

BAKER’S TIP:
The secret to a good millionaire’s shortbread is to make a caramel that sets enough so that it does not squish out of the sides on cutting, and a chocolate topping that is soft enough to cut easily. Add a little butter to the chocolate to soften it slightly, and gently cook the caramel until thickened to achieve a perfect result.

Marbled Millionaire’s Shortbread