Next on tour of French Patisserie is a classic combination of coffee, chocolate and cream (the French Tiramisu) and a homage to my other passion, the Opera cake. This cake is technically difficult but melts in the mouth, when made correctly, and is almost as tasty as Tenor Jonas Kauffmann (Exhibit A https://www.youtube.com/watch?v=RzLR1OuDaKY&list=PL4_Y5duTlUpkLbLPRZ16uNo1Xxo_Fcr8Z). It was made famous in the 19th century by French Patissierie Dalloyau, which just so happens to be in the shadow of the Opera Garnier the building on which the pastry is based on. I assume that the many decadent layers of the cake are meant to mirror the decadent layers of the Opera Garnier. I should hopefully end up with perfect contrasting cream and brown layers with a smooth, shiny chocolate ganache on top.
The First Challenge is the Almond sponge, I found the key here was to be very gentle with the mix, especially folding the egg whites, be very accurate with the measurements and trust your oven (i.e don’t open the door too early during cooking or the cake will sink). I also made this sponge mix in two batches (I only had one tin and didn’t want the mixture to deflate too much between cooking, of course if you happen to have 4 swiss roll tins lying around handy, you’re fine.)
Almond Sponge (serves 10)
150g icing sugar
5 tbsp flour
pinch of salt
140g ground almonds
1tsp vanilla extract
6 eggs
30g butter, melted and cooled
6 egg whites
2tbsp caster sugar
1. Mix the icing sugar, flour, salt and almonds together. Whisk in the eggs one at a time slowly before adding the vanilla. Then add the butter.
2. Whisk the egg whites to soft peaks, (you should be able to turn the bowl upside down on your head without the eggs falling out – I greatly enjoy doing this to other people). Add the sugar carefully and whisk to shiny peaks. Mix 1/3 into the almond mix, whisking together. Fold (using a metal spoon in a folding action) the remainder of the egg whites into the mix.
3. Spread a thin layer onto a lined swiss roll tin (34.5x 24.4cm). Make sure to use a palate knife to spread the mix to the ages, but try not to overwork it or it will lose the rise. Bake at 220oC for 6-8mins, until golden brown. Turn out onto a wire rack to cool. Repeat 4 times.
For the Coffee Syrup
300ml water
150g sugar
3tsp expresso powder (I also like to add a drop of vanilla extract)
1. Stir the ingredients together until dissolved over a low heat, bring to the boil, boil for 1-2mins, remove from the heat.
For the Coffee Buttercream
4 egg yolks
150g sugar
40ml water
pinch of salt
300g butter
2tsp expresso powder dissolved into 2 tsp boiling water
1. For this recipe you really need a kitchen aid (no-hand mixer) or a hand held electric whisk (but you may need help). It’s quite hard to do it without… Whisk the 4 egg yolks on high for 5mins until light and creamy.
2. Meanwhile heat the sugar, water and salt in a pan until boiling. Boil until you get a clear syrupy consistency (roughly 115oC).
3. Immediately pour into the egg yolks little by little, like making mayonnaise, while the mix is still mixing. Add a bit then whisk some more and repeat. You should end up with a lighter pale mousse consistency. Keep whisking until cooled to room temperature (feel the sides of the bowl, if it is too warm the butter will melt into the mix and you won’t get the desired consistency.)
4. Add the butter bit by bit and whisk until you get a white creamy mix. Add the expresso, cooled.
For the Ganache
100g dark chocolate
15ml cream
60ml whole milk
(optional: 20ml white rum)
50g butter
1. Chop the dark chocolate finely and pour into a bowl. Heat the cream, (rum) and milk together and bring to the boil. Immediately pour over the chocolate and leave for 2-3mins. The chocolate should have melted. Mix to a smooth melted chocolate consistency if need be add more dark chocolate to achieve desired consistency and blast for 5-10secs in the microwave at a time to heat a little, before beating to melt. When chocolate is melted add the butter and mix till melted. Leave to cool to a spreadable consistency.
For the Chocolate Glaze
200g dark chocolate
60g butter
1. Melt chocolate and butter together. Reserve some in a piping bag to pipe.
To Construct
1. Take 1 of the sponges. Lay down with the non-parchment side facing up. Temper 150g chocolate. (Melt at 20 sec intervals until almost all is melted – there should be a few lumps, take out and stir till all the lumps have melted = easy tempered chocolate). Spread this over the sponge in a thin layer, then leave to set in the fridge for 5mins (you don’t want it completely hard). Flip onto a cake board/whatever you want to serve the cake off. The chocolate bottom will make it easier to take the slices off the board later.
2. Soak the first sponge with coffee syrup, the more the better, but make sure to dab not pour the syrup over or you will just end up with a disintegrated sponge. Apply your first layer of buttercream, using a palate knife to smooth it down to about 1/2 cm thick.
3. Top with the next sponge, parchment paper up. Remove the parchment paper and soak with coffee syrup. (NB you may want to refrigerate the cake between layers if your kitchen is very hot. But the buttercream will have to sit out a little so it can be spread.
4. Spread with chocolate ganache, then top with the next sponge and soak with syrup. Spread with more buttercream, top with the final sponge and soak with syrup.
5. Finally spread one more layer of buttercream, thinner than the others. This is mostly just to make the top smooth and fill in the cracks.
6. Finally pour over the glaze, spread evenly and quickly (mine wasn’t as even as I would’ve liked and the key is speed.)
7. Let set for a little, then take a serrated knife and cut down each side to trim the edges. Keep refrigerated till served.