This is one of the first courses served at Le Balico, my favourite restaurant in Menton. It's called Flan de Poissons which is confusing for an English speaking person as we think of 'flan' as a sort of pastry tart. Here it means a mousse or cream. The dictionary translates flan - amongst other things - as a mould, and perhaps that's the point - this fish mousse is made in a round mould. None of which matters in the slightest, because I can tell you it's delicious and even better with a glass of white wine.
Note: Since posting this, sadly Le Balico has been sold and is now under new management.