Peel and finely dice the shallots. Finely dice the gherkins. Wash parsley, shake dry and chop. Dice fillet, chop finely and season with mustard, 2 tablespoons Worchester sauce, a little salt and pepper.
Cut the tartar into quarters and place in heaps on a plate or 4 portion plates. Press a small depression in the middle. Separate eggs, use egg white for other purposes. Put 1 egg yolk in each hollow, sprinkle with some cornichons, shallots, capers, parsley and pepper.
Add the rest of the ingredients and Worcestershire sauce, so that you can season. Serve immediately.