To make the chocolate sponge: Preheat the oven to 180°C.

Line the base and sides of a 20cm spring-form cake tin with greaseproof paper. Melt the chocolate and butter in a metal bowl over a pan of simmering water. Whisk the egg yolks with half the caster sugar for 30 seconds. Stir in the melted chocolate then mix well. Beat the egg whites with the remaining caster sugar, until very stiff , then quickly fold one third of the white mixture into the chocolate mixture. Gently fold in the remaining two thirds then pour into the cake tin.

Place on the middle rack of the oven then bake for 20 minutes. Remove from the oven and allow to cool.

To make the candied parsnip: Run a vegetable peeler down the length of each parsnip then continue until you reach the inner woody flesh. Place a shallow saucepan over a medium heat. Add the sugar and water then allow to dissolve. Add the parsnip peels then carefully stir until coated. Leave to simmer for 15 minutes or until the parsnip curls are sticky and slightly golden.

To make the chocolate ganache: Slowly melt the dark chocolate then combine with the cream and mix to a smooth, silky consistency.

To assemble the cake: Using a round cookiecutter, cut out rounds of chocolate sponge and stack. Spread a generous helping of chocolate ganache between each layer. To serve, top with the candied parsnip curls.

Per serving: 4209.2kJ, 13.3g protein, 72.3g fat, 84.4g carbs