Preparation and cooking time: 30 min
Chilling time: 4 h
200 g dark chocolate, chopped, plus 50 g extra to serve
100 g milk chocolate, chopped
3 tbsp unsalted butter, cubed
500 ml double cream
3 tbsp caster sugar
4 large egg yolks
1 1/2 tsp vanilla extract
150 g blackberries
Combine both chocolates, the butter, and 60 ml cream in an iCook mixing bowl set over a half-filled iCook 3-litre pan of simmering water.
Stir until smooth and evenly melted before removing from the heat and leaving to cool.
In the meantime, whip remaining cream in a larger iCook mixing bowl until firm. Beat the egg yolks with the sugar and vanilla extract in a separate bowl until pale and thick (2–3 minutes)
Gradually whisk the melted chocolate mixture into the egg yolk mixture until smooth and even.
Whisk about one-third of the whipped cream into the chocolate mixture and then fold through most of the remainder until there are no visible streaks of cream left; keep about 2–3 tbsp whipped cream reserved to garnish.
Divide mousse between four serving glasses. Cover and chill for at least 4 hours; chill the reserved whipped cream as well.
When ready to serve, top each mousse with the reserved whipped cream and some blackberries. Grate over more dark chocolate before serving.