You don't necessarily need egg yolk to bind a mayonnaise. Fresh mussel meat also works. Or a combination of the two. And it also gives off an excellent flavour.

Here's how it works: 1) Separate the egg yolk from the egg white 2) Roughly chop the mussel meat and finely puree in a blender with a little olive oil 3) Mix the mussel puree with the egg yolk 4) While stirring constantly, add olive oil in a fine stream until mayo thickens 5) Flavour with lemon juice, sea salt, ground black pepper and a few saffron threads