Floating islands with espresso caramel sauce

This is one of my all-time favourite puddings, with clouds of fluffy sweet meringue hanging low over a sunshine sea of custard. I realised that, as a coffee lover, I had not included it anywhere in the book, so timidly decided to smuggle it into this classic pudding. The result works well. My father used to serve the custard warm and poach the islands in front of us, so you can also cook the dish this way - hot.