Method

• 1.
  Preheat the oven to 200°C (400°F/Gas 6). Line a baking tray with baking paper.
• 2.
  For the chocolate and hazelnut biscotti, add the eggs and sugar to a bowl and whisk together until combined. Sift over the flour, cocoa powder and bicarbonate of soda and stir to form a smooth dough, then add the roasted hazelnuts and mix together with your hands until the nuts are evenly distributed throughout.
• 3.
  Turn the dough out onto a clean, floured work surface and divide into two equal-sized pieces. Roll the dough out into log shapes, then transfer to the prepared baking tray and bake for 15 minutes. Remove from the oven and leave to cool on a wire rack for 10–15 minutes, then cut each log into 2 cm ( ¾ in) pieces using a serrated knife.
• 4.
  Arrange the biscotti pieces on the baking tray on one of their cut sides, then return to the oven and bake for a further 10 minutes, turning halfway through cooking, until dried out. Remove from the oven and leave to cool on a wire rack.
• 5.
  For the raspberry sauce, add all the ingredients to a heavybased saucepan over a medium–low heat. Cook for 15 minutes, stirring occasionally to ensure it doesn’t catch on the bottom, until the berries have broken down into a sauce and the mixture has reduced and thickened enough to coat the back of a spoon.
• 6.
  Pour into a bowl and leave to chill in the fridge until needed.
• 7.
  Put the sugar, dextrose and skim milk powder in a bowl and mix to combine. Put the carob bean powder in a separate bowl. Add 2 tablespoons of the sugar mixture and mix together well.
• 8.
  Add the milk, cream, water and egg yolk to a large heavy-based saucepan over a medium heat and whisk to combine. Whisk in the carob bean powder mixture and continue to heat, whisking in the sugar mixture as you go, until it hits 85°C (185°F).
• 9.
  Remove the pan from the heat, add the mascarpone and blend with a hand-held blender until smooth, then pour into a suitable lidded container and leave to cool in the freezer for 1 hour, or until the mixture drops to 4°C (39°F).
• 10.
  Turn on your gelato maker so it begins the freezing process. Transfer the raspberry sauce and biscotti to the freezer to chill.
• 11.
  Pour the mixture into your gelato maker. Once the mixture reaches –4°C (25°F) or is the consistency of soft-serve ice cream (this should take about 30–45 minutes) detach the canister or scoop the gelato into a pre-cooled lidded container. Place the gelato in a freezer for 30 minutes to harden further.
• 12.
  Roughly chop the chilled biscotti and add to the gelato with the chilled raspberry sauce. Mix together roughly (you want a ripple effect here, so be sure not to overwork the gelato), then transfer to the freezer and leave for at least 1 hour to harden before serving.