Ganache-Coated Chocolate Mousse Dome with Hazelnuts and Strawberry

👨‍🍳 Method

For the Sponge Cake

1. 1
   Preheat the oven to 180°C (355°F).

   ⚙ Preheating the OvenOven

   💡Put things in the oven only once it's reached temperature, after the heating light has gone off: an oven that hasn't reached temperature changes baking times, and the bake burns outside or stays underbaked.
2. 2
   Whip the eggs and the sugar 6 minutes, until the mixture is pale, thick and very fluffy.

   ⚙ WhippingBowlHand mixerorStand mixerorWhisk

   💡With whole eggs, all the rise comes from the whipping: whip until the mixture leaves a ribbon on its surface, and fold in the flour gently so the air doesn't escape.
3. 3
   Add and mix on low speed, just until they are absorbed.
4. 4
   Sift the flour and cocoa over the top and Fold gently, just until the flour is absorbed.

   ⚙ FoldingSilicone spatulaSifter

   💡Fold with a spatula, in broad strokes from the bottom up, and stop when there are no streaks: vigorous mixing knocks the air out of the foam. Add whipped mixtures in stages: a quarter first, to lighten the mixture.

   💡Fold with a spatula, in broad strokes from the bottom up, and stop when there's no dry flour: vigorous mixing of a batter with flour develops gluten.
5. 5
   Spread the batter into a 20 cm round on parchment paper in the pan.

   Baking sheetParchment paper
6. 6
   Bake 9 minutes, until the cake springs back when touched.

   ⚙ BakingOvenBaking sheet

   💡Check by the cue (until…), not just the clock: every oven bakes a little differently.
7. 7
   Let the cake cool completely.

To assemble

1. 8
   Line a 18–20 cm round bowl with plastic wrap, with overhang at the edges.

   BowlPlastic wrap
2. 9
   Coarsely chop half of the hazelnuts and mix with the Nutella spread for the core. Finely chop the rest for garnish.

   KnifeCutting board
3. 10
   Melt the chocolate in a double boiler, stirring, and let it cool slightly.

   Double boiler (bain-marie)
4. 11
   Whip the yolks with the sugar over a pot of simmering water for 4 minutes, until they are thick and hot.

   ⚙ WhippingBowlHand mixerorStand mixerorWhisk
5. 12
   Add the melted chocolate and mix until even.
6. 13
   Whip the cream to soft peaks. Fold it into the chocolate mixture in three additions.

   ⚙ WhippingBowlHand mixerorStand mixerorWhisk

   💡Whip cream very cold, in a chilled bowl with chilled beaters, and stop when it holds firm: overwhipping turns it grainy and buttery.
7. 14
   Pour two thirds of the mousse into the bowl and spread it up the sides, so a hollow forms in the center. Fill the hollow with the core, cover with the rest of the mousse and set the base on top, pressing lightly.

   Offset spatula
8. 15
   Freeze 4 hours.

   Freezer
9. 16
   Finely chop the chocolate and put it in a bowl.

   KnifeCutting boardBowl
10. 17
    Heat the cream until just about to boil and pour over the chocolate. Wait a minute without touching.

    StoveSmall saucepan
11. 18
    Stir gently from the center outward, until you get a smooth, glossy cream.

    💡Stir gently from the center outward: vigorous stirring beats in air, and the ganache loses its shine.
12. 19
    Cool 10 minutes.
13. 20
    Turn the frozen dome out onto a tray, peel off the plastic wrap and pour the ganache over the top. Smooth with a wide spatula, so the ganache covers the dome down to the base.

    Offset spatula
14. 21
    Sprinkle the rest of the hazelnuts, chopped, on top and set the strawberries in the center.
15. 22
    Move to the fridge for 2 hours, until the mousse thaws and turns soft.

    Refrigerator