Jerusalem artichoke and chocolate brownie, hazelnut ice cream, caramel and blackcurrant

For the black-fermented artichokes, place the Jerusalem artichoke peelings in a vacuum packing bag, then vacuum seal. Ferment at a constant 60°C temperature for 30 days. Weigh out 70g and set aside (this will make around 500g)

For the Jerusalem artichoke ice cream, dice the Jerusalem artichokes (reserve the peel for the skin crunch), then sauté in butter until golden and aromatic

Meanwhile, place the milk, cream, glucose and salt in a small saucepan and bring to the boil. Whisk the egg yolks in a heatproof bowl, then slowly incorporate the milk and cream mixture, whisking continuously. Return the custard base to the pan and cook until it reaches a temperature of 84°C, stirring constantly

Whisk in the gelatine, stabiliser and cooked artichokes, then blend until smooth. Cool then chill the ice cream base for a minimum of 6 hours

Once the ice cream base is chilled, freeze it in Pacojet containers at -20°C (or churn in an ice cream machine)

For the hazelnut cream, first make the hazelnut milk. Warm the milk in a saucepan then place in a blender with the hazelnuts. Blend until smooth then strain through a fine mesh sieve to obtain a smooth, aromatic milk. Weight out 65g (this will make more than you need)

Bring the cream, butter and white chocolate to the boil, then remove from the heat. Add the gelatine, hazelnut praline and the 65g of hazelnut milk to the cream, mixing until smooth. Cool then chill the cream for at least 4 hours until fully set

Once the hazelnut cream has set, transfer it to a blender and blend to a smooth, light cream. Set aside in the fridge until needed

For the Jerusalem artichoke brownie, preheat the oven to 170°C. Combine the water, cocoa powder, butter and salt in a saucepan and gently heat until fully melted, smooth and emulsified

Add the sugar and flour, stirring continuously until the mixture thickens slightly, then cook gently for around 5 minutes. Transfer to a large bowl and allow to cool slightly

Meanwhile, place the 70g of fermented Jerusalem artichoke, eggs and soured cream into a blender and blend until smooth

Fold the egg mixture into the chocolate base to form a rich batter

Pour 50g portions into greased moulds and bake for approximately 15 minutes. Cool on a wire rack then remove from the moulds and store at room temperature

For the Jerusalem artichoke skin crunch, heat the vegetable oil in a deep pan over a medium-high heat, or preheat a deep-fat fryer to 180°C. Deep-fry the reserved artichoke skins until crispy, working in batches if needed, then remove with a slotted spoon to kitchen paper to drain. Leave to cool then weigh out 25g (this will make more than you need)

Melt the milk chocolate gently over a bain-marie, then fold through the fried artichoke skins, flaked almonds and rapeseed oil. Spread onto a non-stick baking mat or baking sheet lined with parchment paper (or shape as desired) and allow to set

For the blackcurrant gel, combine some of the blackcurrant purée with the water and sugar, bring to the boil, then add agar agar and cook briefly

Incorporate the remaining purée then strain through a sieve into a container. Once cool, chill in the fridge until fully set. Blend into a smooth gel then transfer to a piping bag and set aside

For the Jerusalem artichoke caramel, first juice the artichokes. Place them in a juicer and process, discarding the pulp. Weigh out 200ml and reduce it with the sugar and liquid glucose until the mixture is lightly caramelised. Stir through the butter and cream to create a smooth, glossy caramel then transfer to a squeezy bottle and set aside

To serve, Pacotise the Jerusalem artichoke ice cream (if needed) or just remove it from the freezer for a few minutes to soften

Spoon some hazelnut cream into serving bowls, and smooth with the back of a spoon. Pipe on some blackcurrant jam and place the brownies on top. Cover generously with the Jerusalem artichoke caramel

In separate serving bowls, arrange some of the Jerusalem artichoke skin crunch in the bottom of the bowls. Add a spoonful of the Jerusalem artichoke ice cream into each bowl and finish with some more caramel piped over the top. Garnish the brownies with a dusting of gold powder