Chocolate Royal (aka "Royal au Chocolat", "Versaillais", "Trianon")
https://www.bakinglikeachef.com/royal-chocolate-cake-by-christophe-felder/ see also: https://www.tartedor.nl/chocolate-royal/
Ingredients:
For the dacquoise:
- 3 ½ tablespoons (55g) egg whites (about 1.5 eggs worth of white, if each egg is 60g)
- 2 ½ tablespoons (35g) granulated sugar
- ½ cup + 1 teaspoon (65g) powdered/icing sugar
- ⅓ cup (30g) almond flour
- 2 tablespoons (15g) hazelnut flour
For the crunchy praline feuilletine:
- 1.7 oz (50g) crêpes dentelles Gavottes
- 1.7 oz (50g) milk chocolate
- 1.7 oz (50g) hazelnut spread Nutella
- 1.7 oz (50g) hazelnut praline paste
For the chocolate mousse:
- 2 cup + 3 tablespoons (500ml) whipping cream
- 5 tablespoons (75ml) whole milk
- 7 oz (200g) dark chocolate
For the cocoa mirror glaze:
- ⅔ cup + 4 ½ tablespoons (210g) granulated sugar
- 5 tablespoons (75ml) water
- 9 ½ tablespoons (70g) unsweetened cocoa powder
- ½ cup + 2 tablespoons (145ml) whipping cream
- 3 ⅓ gelatin sheets (or 8g powdered gelatin bloomed in ¼ cup (60ml) cold water)
Instructions:
To make the dacquoise (almond biscuit similar to a coarse macaron):
- Preheat the oven to 335°F / 170°C.
- Sift powdered (icing) sugar, almond flour, and hazelnut flour through a flour sifter.
- In a separate bowl, whisk egg whites and gradually add granulated sugar until stiff peaks.
- Once the meringue is ready, add icing sugar/flour mixture and gently fold in with a spatula.
- Transfer the preparation in a pastry bag, fitted with an Ateco plain pastry tip 809.
- Adjust a mousse cake mold to 7 inches/18 cm in diameter, and line it with parchment paper.
- Pipe a large flat disc inside the mold using a spiral pattern, or simply use a spoon to flatten it out.
- Bake for 20 to 25 minutes.
- Let it cool in a frame.
To make the crunchy praline feuilletine:
- Crush crepes Gavottes roughly with your hands or a rolling pin.
- Melt milk chocolate in a bain-marie/water bath.
- Mix hazelnut praline, Nutella, and broken crepes in a bowl.
- Add melted chocolate and mix again.
- Loosen the dacquoise from the mold, but keep it inside.
- Pour the crunchy mixture over dacquoise, spread it in a thin layer.
- Then remove the mold and freeze the dacquoise for about 10 to 15 minutes.
To make the chocolate mousse:
- Whip the cold whipping cream in a bowl to get the whipped cream and refrigerate. (Note: philips blender with a whipping attachment can only reliably whip 1 cup at a time, so whip in 2 batches)
- Melt dark chocolate broken into small pieces in a bain-marie/water bath.
- Bring milk to a boil, pour it over the melted chocolate, and mix with a rubber spatula until smooth.
- When the chocolate mixture is lukewarm, add it to the whipped cream and mix with a spatula as fast as possible.
- Transfer the mousse to a pastry bag with a plain tip.
To assemble the cake:
- Seal one side of the 8 inches/20 cm cake ring with a plastic film and place it on a wooden board or a baking sheet.
- Insert an acetate collar inside the ring.
- Poach the chocolate mousse in the mold, trying to raise it on the sides of the ring using a rubber spatula.
- Take the dacquoise disk from the freezer, turn it over and place it over the mousse (dacquoise side up).
- Slightly press the disk and remove the excess mousse with a bent spatula.
- Cover with a plastic film and freeze for at least 5 hours.
To make the cocoa mirror glaze:
- Soak gelatin sheets in cold water for 10 minutes.
- Heat whipping cream over low heat and set aside.
- Pour water and sugar into a saucepan and bring to a boil.
- Once the sugar syrup starts boilng actively, pour it over the sifted cocoa powder and gently mix, trying not to incorporate air.
- Add the drained gelatin and mix it with a hand blender.
- Then pour hot whipping cream and mix again.
- Pass the mixture through a fine-mesh sieve and mix with a hand blender.
- Let the glaze cool down to 86°F/30°C.
To glaze the cake:
- Take the dessert out of the freezer.
- Place the cake on a wire rack or a plate, which is itself placed on a baking sheet to collect the excess glaze.
- Remove the plastic film, mold (heat the sides of the ring with a blowtorch), and acetate collar.
- Pour the glaze over the cake and remove the excess glaze with a bent spatula, passing it over the top once.
- Transfer the dessert to a cake board using two metal spatulas.
- Place the cake in the fridge to thaw for 3 to 4 hours.
Notes:
- Do not over whisk egg whites while making the dacquoise. They have to be slightly firm to incorporate the nut flour.
- Spread the chocolate mousse well inside the mold, using a rubber spatula to avoid trapping air in the cake.
- Once the cocoa mirror glaze is applied, use a bent metal spatula to remove the excess with a single pass over the top of the cake to avoid making marks.
- Store the decorated cake for 2 to 3 days in the fridge.
- Take the dessert out of the fridge about 20 minutes before tasting (the cold temperature alters the taste of chocolate).