Dark Chocolate Mousse Recipe

Melt chocolate and butter

Chop the chocolate into small pieces so it melts evenly. In a heatproof bowl set over (but not touching) simmering water (double boiler), combine the chopped chocolate and 30 g butter. Stir occasionally until fully melted and glossy. Remove from heat and let cool slightly (3–5 minutes).

Prepare egg yolks

While the chocolate cools, whisk the 3 egg yolks with 20 g of the granulated sugar (reserve the rest for the whites) and 1 tsp vanilla extract until the mixture is pale and slightly thickened (about 1–2 minutes by hand or 30 seconds with an electric mixer). Temper the yolks by whisking a spoonful of the warm melted chocolate into the yolks, then slowly whisk the rest of the chocolate into the yolk mixture until smooth and fully combined. Add a pinch of salt.

Whip cream

In a chilled bowl, whip 150 ml cold heavy cream to soft peaks — it should fold slowly and hold shape but still be silky. Fold one-third of the whipped cream into the chocolate-yolk mixture to lighten it, then gently fold in the remaining cream until uniform. Use a rubber spatula and fold with wide strokes to keep air in the mousse.

Whisk egg whites

In a very clean bowl, whisk the 3 egg whites with the remaining 20 g granulated sugar and a pinch of salt to medium-stiff peaks (peaks that hold but still have a slight curl). Gently fold one spoonful of the beaten egg whites into the chocolate mixture to loosen it, then carefully fold in the rest in two additions until no white streaks remain. Work gently to retain volume.

Portion and chill

Spoon or pipe the mousse into serving glasses or ramekins, leaving room on top for the caramelised clementines and hazelnuts. Smooth the tops, cover with plastic wrap (touching the mousse surface to prevent a skin), and chill in the refrigerator for at least 2 hours, preferably 3–4 hours, until set.

Prepare fruit: Peel the clementines, remove any pith and membranes where possible, and separate into segments. Pat segments dry on paper towel to remove excess juice.

Caramelise: In a medium nonstick skillet, melt 20 g butter over medium heat. Add 40 g brown sugar and stir until it dissolves and begins to bubble gently (about 1–2 minutes). Add the clementine segments in a single layer and cook 1–2 minutes per side, spooning the caramel over them. Add 1 tbsp lemon juice and 1 tbsp orange liqueur (if using) and cook another 30 seconds to concentrate flavors. Remove from heat and let cool slightly; the caramel will thicken as it cools. Reserve any pan juices to drizzle over mousse when serving.

Toast nuts: Preheat oven to 175°C (350°F). Spread 80 g hazelnuts in a single layer on a baking sheet and toast for 8–10 minutes until fragrant and skins blister (watch closely to avoid burning). If you prefer skinless nuts, wrap the hot hazelnuts in a clean kitchen towel and rub to remove skins; it is okay if some skins remain.

Optional caramelised crunch: For a candied finish, return the toasted hazelnuts to a dry skillet over medium heat, sprinkle 1 tbsp coarse sugar and stir until sugar melts and coats the nuts, about 1–2 minutes. Immediately transfer nuts to parchment to cool and separate. When cool, roughly chop the nuts and toss with 1/4 tsp sea salt.

Assemble: Remove mousse from refrigerator when ready to serve. Spoon 2–3 caramelised clementine segments onto each mousse portion, drizzle a little reserved caramel pan juice over them, and scatter a tablespoon of the toasted (and chopped) hazelnuts on top.

Garnish: Finish each serving with a light dusting of grated dark chocolate or cocoa powder. Serve chilled.