Salted Butter Caramel Opera

Ingredients:

Joconde biscuit:
125 g almond powder
125 g icing sugar
35 g flour
4 whole eggs
4 egg whites
30 g caster sugar
30 g melted butter

Salted caramel buttercream:
100 g sugar
40 g semi-salted butter
100 ml full-fat liquid cream
3 egg yolks
150 g soft butter, softened

Chocolate ganache:
200 g dark chocolate (70%)
200 ml full-fat liquid cream

Soaking syrup:
100 ml water
50 g sugar
1 tablespoon vanilla extract

Chocolate icing (optional):
100 g dark chocolate

20 g butter

Instructions:

Instruction of the Joconde biscuit:
Preheat the oven to 180°C. Sift the almond powder, icing sugar and flour. Add the whole eggs and mix until you have a smooth dough.
Beat the egg whites with the caster sugar until stiff.
Gently fold the beaten egg whites into the dough, then add the melted butter.
Spread the dough in a thin layer on a baking sheet covered with baking paper (about 1 cm thick).

Bake for 10 minutes, until the biscuit is lightly golden. Leave to cool, then cut out three rectangles of the same size.

Salted caramel buttercream:

In a saucepan, melt the sugar over medium heat until you have a golden caramel. Off the heat, add the semi-salted butter while stirring, then the hot liquid cream little by little.
Return to the heat and mix until you have a smooth texture. Leave to cool.

In a bowl, whisk the egg yolks. Slowly add the warm caramel while whisking to avoid cooking the eggs.
Then gradually add the softened butter, whisking until you obtain a smooth and homogeneous cream.

Chocolate ganache:
Heat the cream until it simmers, then pour it over the chopped dark chocolate.

Mix until you obtain a smooth ganache. Let cool to room temperature.

Soaking syrup:

Heat the water and sugar in a saucepan until the sugar has dissolved. Add the vanilla extract and let cool.

Assembly:
Soak the first rectangle of biscuit with the syrup.
Spread a layer of salted caramel buttercream.

Place the second rectangle of biscuit on top, soak it as well, then spread a layer of chocolate ganache.
Repeat with the last rectangle of biscuit, soak it, and finish with a thin layer of chocolate ganache to even out the top.

Let the cake rest in the refrigerator for at least 2 hours.

Chocolate Icing (optional):
Melt the chocolate with the butter, then pour it over the cooled cake for a glossy finish. Spread quickly with a spatula.

Finishing:
Trim the edges of the cake to obtain a neat and clean rectangle.
Decorate with caramel pieces, chocolate pearls or a chocolate inscription according to your desires.

Serving:
Serve in thin slices to enjoy the balance between the soft biscuit, the salted caramel and the intense chocolate. Bon appétit!

Origin of Salted Butter Caramel Opera:

The invention of the cake was claimed by Gaston Lenôtre in the 1960s, but could be due to the Dalloyau house. According to the latter, the opera was created in 1955 by Cyriaque Gavillon. According to sources, it was named thus by Andrée Gavillon, the pastry chef's wife, either because of its similarity to the stage of the Garnier opera, or in homage to the dancers of the Opera who came to the shop. This last version is that of the Grand Larousse gastronomique in 2007.

It should be noted that in 1899, the pastry shop of the Grand Hôtel, opened in February at 1 rue Auber, opposite the Garnier opera, published advertisements in several newspapers, mentioning among its specialties an "opera cake". The press cites it, as well as the "plum-cake", as a must of this house frequented by a chic clientele. Shortly before the opening of this pastry shop by the Grand Hôtel de Paris, the latter offered an Opéra ice cream bomb. Finally, the mention of "opéra cake" appears on the menu of dinners served at the beginning of the 20th century. But there is no indication that these cakes are identical to the opera claimed by Dalloyau and Lenôtre. Furthermore, other desserts bear the name "opéra" (among them a charlotte, a crème renversée and a crème caramel).