Cake issues: Double Espresso & Brazil nut cake

Double Espresso & Brazil Nut Cake (troublesome little ******)

I baked (for the first time) a double espresso & brazil nut cake, which I found in a supplement from the Guardian (given to me about 4 yrs ago).

The cake was for the October gathering of Clandestine Cake Club I didn't do a practise cake and just went for it, was this my undoing?

And, I made an adjustment to the recipe: instead of using espresso powder, I used ristretto nespresso coffee.  This is a number-10 rating on the coffee scale, which I'd equate to an espresso hit.  However, when 'dispensed' through the machine it's liquid, and the recipe asked for powder.  However I took this into account by reducing the amount of milk the recipe asked for, hoping that would fix it.

It was a sloppy mixture, and I went through a whole raft of emotions in the mixing process, and I didn't trust the process and added another 50g flour, because it just looked far too wet.  Was this my undoing?

When cooked it looked fine.  I cooled it overnight and kept it in an airtight container.  The night before cake club I mixed up water icing and coffee, filled it, and topped it in icing, dressed it in brazil nuts (in a pretty flower pattern) and put it in the fridge.  Was this my undoing?

In the morning, the top had slid off the cake a little bit and a giant earthquake type crack had appeared across the cake (taking a lot of the icing in at the same time).  Not sure why this had happened, and did a quick repair job of a second coat of icing, removing and crushing the nuts.

The taste: at the Clandestine Cake Club I had a few people tell me how nice it was, one person said that it was as nice as her granny used to make (a fantasic compliment to receive).

But for me, it didn't have that great big woah, smack in the mouth coffee hit that I was looking for, and it also lacked moisture that I wanted too.

Next time...
I will use espresso powder
I will make sure there is a next time.