Marbled chocolate slice with rich chocolate sauce, rosé sorbet and sablé biscuits

Ingredients
For the rosé sorbet
175g/6oz caster sugar

350ml/12fl oz water

250ml/9fl oz rosé wine

5 fresh mint leaves, to garnish

For the marble slice
3 free-range eggs

100g/3½oz caster sugar

1 orange, zest only

100g/3½oz plain flour

3 tsp baking powder

100g/3½oz dark chocolate, chopped

100g/3½oz white chocolate, chopped

100g/3½oz unsalted butter, chopped

butter, for greasing

For the sablé biscuits
50g/1¾oz plain flour, sifted

40g/1½oz unsalted butter, chilled

50g/1¾oz caster sugar

½ lemon, zest only

1 free-range egg yolk

1 tbsp icing sugar, for dusting

For the chocolate sauce
100g/3½oz dark chocolate, minimum 70% cocoa solids

5 tbsp whole milk

1½ tbsp double cream

25g/1oz caster sugar

25g/1oz unsalted butter, diced

Preparation method
1.To make the sorbet, mix the sugar and water in a saucepan, stirring until the sugar has dissolved, then bring to a boil and gently simmer for five minutes. Leave to cool slightly, then add the rosé wine. When completely cold, transfer to an ice cream machine and churn until smooth and frozen through. Transfer to a plastic container with a lid and keep in the freezer until serving.

2.Meanwhile, make the marble slice. Preheat the oven to 170C/325F/Gas 3. Grease the sides of a 20cm x 20cm/8in x 8in baking tin and line the base with baking parchment.

3.Place the eggs, sugar and orange zest in a large bowl and beat using an electric whisk for 3-4 minutes until light and frothy. Sift the flour and baking powder in a separate bowl, then add the dry ingredients to the egg mixture and beat for a further 30 seconds until smooth. Divide the mixture between two bowls. Melt the two types of chocolate in separate bowls set over pans of simmering water with 50g/1¾oz of butter in each. Using the electric whisk, beat the melted white chocolate into one bowl of cake batter and the dark chocolate into the other.

4.Pour the cake batters into the prepared cake tin and swirl a wooden skewer or sharp knife through the two mixtures to create a marbled effect. Bake in the preheated oven for 20-25 minutes until cooked - a skewer should come out clean when inserted into the centre of the cake. Leave to cool in the tin for five minutes before transferring onto a wire cooling rack to cool completely.

5.To make the sablé biscuits, place all ingredients except the icing sugar into a food processor and pulse until the mixture forms into a dough. Turn out onto a lightly-floured surface and knead gently until smooth. Wrap in cling film and chill in the fridge for 30 minutes. Increase the oven temperature to 180C/350F/Gas 4 and line a baking tray with baking parchment.

6.Place the sablé dough between two pieces of baking parchment and roll out to a thickness of 3mm/⅛in. Using a 7cm/2¾in round pastry cutter, cut discs of the dough and transfer to the baking tray. Place in the freezer for five minutes, then bake for 6-8 minutes. Leave to cool and dust with icing sugar before serving.

7.For the chocolate sauce, melt the dark chocolate in a bowl set over a pan of simmering water. In a separate saucepan bring the milk, cream and sugar to a gentle boil, then whisk into the melted chocolate. Pass through a fine sieve into a clean saucepan and then gradually whisk in the butter. Reheat gently before serving.

8.To serve, trim the cake and cut into rectangular slices and serve with the sauce, sablé biscuits and sorbet. Garnish with sprigs of fresh mint