Help with chocolate sponge recipe

[Amintika]

 I've been recently trying to make the following recipe: https://www.greatbritishchefs.com/recipes/black-forest-gateau-recipe

Most of the components work fine, but for the life of me I can't get the chocolate sponge to work, perhaps in part because I find the recipe ambiguous. Hence I'd really appreciate the input of someone more experienced than myself. Steps 1 and 2 cover the sponge, and it's step 2 that I find difficult:

Meanwhile, melt the chocolate in a bain marie. In a separate bowl, sift the cocoa powder over the egg yolks, whisking thoroughly to combine. Slowly pour and continue to whisk in the melted butter. Remove from the heat and allow to cool before gently folding in the meringue, 1/3 at a time to incorporate as much air as possible

 

Firstly, do I put the melted butter into the egg yolk and cocoa mixture, or into the melted chocolate? Secondly do I combine these two elements before folding into the meringue, or are they folded in individually? In the past I've always tried to combine them before folding and I find that the mixture splits rapidly, irrespecitve of whether the butter has gone into the yolks or into the chocolate.

Unfortunately I don't have an photos, but any help (or links to similar recipes so I can compare) would be very helpful.
 

[pastrygirl]

Hmm, that is ambiguous.  I think I'd add everything to the egg yolks - whisk in cocoa, then butter, then melted chocolate, then fold in the whipped whites. 

[Amintika]

7 minutes ago, pastrygirl said:

Hmm, that is ambiguous.  I think I'd add everything to the egg yolks - whisk in cocoa, then butter, then melted chocolate, then fold in the whipped whites. 

Thanks for the input. That was my first instinct, the yolks with the cocoa (100g yolk to 20g cocoa) has the consistency of a very thick paste, as you add the butter it does slacken but remains thicker than say a mayonaise or a ganache. As you add the melted chocolate to this something splits out - I think perhaps the cocoa butter as you end up with many little bits of black chocolate sludge coated in a thin transparant oil. On my third attempt I 'rescued' it by adding about a tablespoon of boiling water and slowly mixing it back together - almost like saving an hollandaise but with boiling water rather than cold water. I've since tried to carefully heat everything up to ~50°C before combining to see if that would help, but alas not. It's left me quite perplexed to be honest.

Edited July 18, 2018 by Amintika (log)

[pastrygirl]

11 minutes ago, Amintika said:

Thanks for the input. That was my first instinct, the yolks with the cocoa (100g yolk to 20g cocoa) has the consistency of a very thick paste, as you add the butter it does slacken but remains thicker than say a mayonaise or a ganache. As you add the melted chocolate to this something splits out - I think perhaps the cocoa butter as you end up with many little bits of black chocolate sludge coated in a thin transparant oil. On my third attempt I 'rescued' it by adding about a tablespoon of boiling water and slowly mixing it back together - almost like saving an hollandaise but with boiling water rather than cold water. I've since tried to carefully heat everything up to ~50°C before combining to see if that would help, but alas not. It's left me quite perplexed to be honest.

 

 

So that means there is not enough water in the egg yolks alone to emulsify with all of the fat in the butter and chocolate.  There's a little water in butter too but not enough. 

 

So I think you need to either add the melted chocolate last (after folding in the egg whites, which have a lot of water), add enough water to the yolks to keep things from separating, or even try beating whole eggs with sugar until fluffy then stirring in chocolate, cocoa, and butter. 

[Amintika]

3 minutes ago, pastrygirl said:

 

So that means there is not enough water in the egg yolks alone to emulsify with all of the fat in the butter and chocolate.  There's a little water in butter too but not enough. 

 

So I think you need to either add the melted chocolate last (after folding in the egg whites, which have a lot of water), add enough water to the yolks to keep things from separating, or even try beating whole eggs with sugar until fluffy then stirring in chocolate, cocoa, and butter. 

 

Ahah, that makes a lot of sense. I had noticed that the egg yolks I'd been getting recently were surprisingly viscous. Thanks for the advice, I'll try that tomorrow and see how it goes.

[Amintika]

 Just had a chance to try the recipe again, addded 20g of water to 100g of yolks before adding the cocoa and it emulsified without any issues. Sponge turns out fine then. Thanks for the help!
 

[pastrygirl]

Hooray!

[keychris]

You may also like to try mixing a little of the egg white with the chocolate mixture to lighten it up before folding the rest in, it's easier to fold if the two components are somewhat close in consistency - if you have thick heavy chocolate mixture and soft fluffy wgg whites, folding might take a while