There’s something so enticing about fancy, fancy Parisian style desserts. This opera cake had all the makings of a showstopping creation – three layers of syrup-soaked joconde sponge, coffee buttercream, chocolate ganache, and the final layer of chocolate glaze.
This cake is not for the faint-hearted baker. After making it, I realise I could never be a contestant on the Great British Bake Off. You know when you see them panicking about techniques they’ve never practised, and the cake tins and bowls start piling up, and Mel and Sue start counting down….
The making of this Gateau L’Opera was kinda like that.
I used the recipe from Dorie Greenspan’s Paris Sweets, having heard many a good thing about both author and cookbook.
The coffee syrup was easy, just boiling together water, sugar and coffee in a pan. Next, the coffee buttercream. This required the makings of a sugar syrup that is then beaten into whisked eggs, before mixing in softened room-temperature butter. Room temperature is a funny thing to gauge – I mean, is your kitchen the same steady temperature the whole year round? Anyway, needless to say, I added the butter when it was decidedly not room temperature. The buttercream immediately curdled, and required about 20 minutes solid beating with the electric whisk before it relaxed into something softer and more cohesive.
Next, the joconde. It looked similar to the process of making a swiss roll, but with the addition of ground almonds and melted butter. I might add that I have never successfully made a non-eggy swiss roll, but nevertheless, continued on. The mixtures were whisked, combined, and I carefully poured in one-third of the batter into my prepared cake tin.
Then horror of horrors, realisation struck that I had forgotten to add the melted butter. In a panic, I scraped the batter back into the bowl, threw in the melted butter, gave it a stir and hoped for the best. At long last, into the oven went sponge numero un.
Things seemed to be going ok at this point. The first sponge came out of the oven. It looked alright, though to my nose I could still detect that eggy undertone. Sponge two went in. I scraped up the batter for sponge 3, and there to my disgust, was a large clot of solidified butter floating at the bottom of the bowl. The butter hadn’t mixed into the batter after all.
I’d all but given up now, but used up so much ingredients-wise, that I thought I might as well carry on and assemble the whole thing. The ganache went on, the sponges were brushed with syrup, and finally I glazed, trimmed, and chilled the whole thing.
Finally, the taste test. Luckily, I had plenty of cut-offs to choose from. Unfortunately, I’ve never eaten a true Gateau L’Opéra before, so I didn’t have a source for comparison. However, this was really delicious. The cake had a light, delicately melty texture. The coffee and chocolate flavours are strong, and meld perfectly together. Despite my fears, the joconde wasn’t eggy at all, and the liberal lashings of coffee syrup kept it from being dry.
The cake was enormous (I used 13 eggs!) and probably large enough to feed at least 30 people! I cut out 8 fingers, and put the remaining rectangle into the freezer for another occasion.
Given the difficulty, and level of faff required making this, I don’t think I’ll be repeating it anytime soon, not without at least practising the individual skills required for making the joconde and the buttercream. Given the size, I’d want to halve the recipe too, although Dorie advised you not to, as it throws the proportions of the ingredients off.
If you want to have a go at making this cake too, Edd Kimber has adapted the recipe I used, and it can be found here.