Today we’re going to make a delicious Gâteau opéra. It's a traditional Parisian cake made from chocolate and coffee. I made a video about it many years ago and this time I tried to improve this beautiful classic.
The coffee syrup
250 grams | sugar |
50 grams | water |
250 grams | water |
40 grams | coffee beans |
Mix the sugar with the 50 grams of water and caramelize this on a medium heat. Then while stirring add the 250 grams of water and bring it to a boil once more. Now pour it in a preserving jar and add the coffee beans. Close it up and let it marinade in your fridge for at least 1 day.
The coffee praline
200 grams | sugar |
50 grams | water |
160 grams | hazelnuts |
1 | vanilla pod |
20 grams | coffee beans |
Mix the sugar with the water and caramelize till golden. Now add the hazelnuts and caramelize it for another 2 minutes. Then add the vanilla pod and the coffee beans. Caramelize it for another minute and then transfer it on some parchment paper and let it cool down. Then transfer it into a wet grinder and grind it into a smooth praline. You can also blend it in a blender, but it’s not going to be as smooth. Once it’s smooth pour it into a bowl.
The whipped praline ganache
1,5 leaves or 2.5 grams | gelatin |
60 grams | cream |
20 grams | milk |
60 grams | coffee praline |
70 grams | white chocolate |
140 grams | cream |
First soak the gelatin in cold water. Then pour the the 60 grams of cream into a saucepan together with the milk and the coffee praline. Now while stirring bring, it to a boil. Then dissolve the gelatin and add the white chocolate. Emulsify this. Once the ganache is emulsified transfer it into a bowl and add the 140 grams of cold cream. Now blend this for 15 seconds and then let it set in your fridge for at least 5 hours.
The chocolate biscuit
70 grams | egg |
25 grams | icing sugar |
60 grams | almond powder |
2 grams | salt |
15 grams | cacao powder |
25 grams | butter |
55 grams | egg white |
40 grams | sugar |
Mix the egg with the icing sugar, the almond powder, the salt, the cacao powder and the butter. Blend this till smooth. Then transfer it into a bowl. Now pour the egg white in a stand mixer and start beating it.
Once a white foam starts to form add the sugar and continue beating till completely stiff. Then add the meringue to the cacao mix and fold everything together. Now pour it on a silicon sheet and spread it. Bake it at 180 degrees Celsius for 15 minutes. Then let it cool down and gently remove the silicon sheet. Cut it with a baking ring. Mine is 16 centimeters.
The coffee ganache
80 grams | sugar |
10 grams | glucose |
20 grams | water |
20 grams | cream |
60 grams | espresso |
60 grams | dark chocolate |
First transfer the sugar in a saucepan. Also add the glucose and the water. Caramelize this till golden. Then turn of the heat and while stirring add the cream, the espresso and the dark chocolate. Now set aside for later. Then transfer the praline ganache into a mixing bowl and beat it for around 2 minutes till stiff peaks have formed. Now transfer it into a piping bag fitted with a round nozzle. Then take the baking ring and place 1 chocolate biscuit on the bottom. Brush it with some of the coffee syrup and then pipe the whipped ganache on top. Spread this. Then pour half of the ganache on the whipped ganache and repeat the whole process once more. So first the biscuit, then the syrup, the whipped ganache and the normal ganache. Now let this set in your freezer. Once it’s frozen remove it from the baking ring and keep it in your freezer for later.
The chocolate mousse
1 leaf or 1,6 grams | gelatin |
50 grams | cream |
90 grams | dark chocolate |
40 grams | sugar |
20 grams | water |
50 grams | egg |
150 grams | cream |
First soak the gelatin in cold water. Then pour the cream into a saucepan and bring it to a boil. Once it’s boiling dissolve the gelatin and add the dark chocolate. Mix this and then transfer it into a bowl. Then mix the with the water and heat this up it it’s 118 degrees Celsius. Meanwhile pour the egg into a mixing bowl and start beating till stiff peaks have formed. Then add the hot sugar syrup to the beaten egg and continue mixing it’s at room temperature. While the eggs are beating pour the cream into a bowl and beat it till it’s at yoghurt thickness.
Now mix the egg mixture with the chocolate ganache. After that add the whipped cream and gently fold this together. Then take a 18 centimeter baking ring and place a coffee bean shaper on the side, all molds I use in this video I had designed and made by Mold Brothers. Click here for more information. Then pour the mousse in the baking ring and swipe the mousse to the side. Press the interior in the mousse and then let it set in your freezer.
The glaze
2 leaves or 3.3 grams | gelatin |
60 grams | water |
70 grams | cream |
110 grams | sugar |
40 grams | cacao powder |
First soak the gelatin in cold water. Then pour the water into a saucepan together with the cream and the sugar. Now bring this to a boil. Once it’s boiling add the cacao powder and while mixing boil it for two minutes. Then dissolve the gelatin. Now pass it through a fine sieve and set aside for later.
The chocolate brush
100 grams | cacao butter |
100 grams | dark chocolate |
First melt the cacao butter on a low heat. Once it’s melted add the dark chocolate and mix it. Then pour it into a brush machine. After that remove the baking ring and the shaper. Now brush a thin layer of the chocolate on the mousse. I always do this outside, because otherwise there will be chocolate everywhere! Then gently place the gateau opera on a plate. Now place a smaller metal ring on top and pour your chocolate glaze in the middle. Remove the ring and let it defrost completely.
The chocolate decoration/ tuille
25 grams | egg white |
25 grams | icing sugar |
25 grams | butter |
15 grams | flour |
10 grams | cacao powder |
Mix the white with the icing sugar, the butter, the flour and the cacao powder. Blend this till smooth. Then spread it on the mold and bake at 160 degrees Celsius for around 15 minutes till crisp. Once that’s done you can brush the tuille to protect it from getting soaky and it will almost look the same as with the chocolate. Now gently place it on the gâteau opéra.