Makes 24 squares

100g walnuts, roughly chopped

50g pistachios, roughly chopped

100g dark chocolate chips

175g unsalted butter, softened, plus extra for greasing

175g caster sugar

3 large eggs

175g self-raising flour

1 tsp baking powder

25g cocoa powder

Pinch of salt

260g salted caramel sauce, chilled

To serve:

Caramel sauce, warmed

1. Preheat the oven to 180 ̊C/160 ̊C fan/gas mark 4. Grease and line a 20 x 30cm baking tin.
2. In a bowl, stir together the walnuts, pistachios and chocolate chips.
3. In a separate bowl, beat together the butter and sugar until light and fluffy. Add the eggs one at a time, beating after each addition.
4. Sieve in the flour, baking powder, cocoa and salt. Stir in two tablespoons of boiling water and whisk together until just combined.
5. Fold in half of the nut mixture. Pour into the prepared tin and smooth the surface.
6. Using the back of a spoon, make small dents in the top and fill them with teaspoonfuls of the chilled salted caramel sauce. Sprinkle the rest of the nut mixture over the cake. Bake for 25 minutes, or until a skewer inserted in the centre comes out clean.
7. Allow to cool in the tin for 10 minutes before carefully using the paper to lift the bake out and transferring to a wire rack to cool completely.
8. Slice into small squares and drizzle with extra caramel, to serve.

Per serving: 193kcals, 12.3g fat (5.5g saturated), 19.4g carbs (11.6g sugars), 4g protein, 1.3g fibre, 0.067g sodium