Roast chicken
Discover just how easy a roast can be with our step-by-step guide to classic roast chicken
Put a very large saucepan of salted water on to boil. Cut the potatoes to marshmallow size, the carrots and celery into dice about two-thirds that size; and the French beans into 2cm/3⁄4in pieces.
Add the vegetables in turn to the pan of boiling water, starting with the potatoes and ending with the peas. Cook until they are all just tender (neither crunchy, nor fondant). Drain and keep warm.
Meanwhile, make the hollandaise. Put the egg yolks, vinegar and lemon juice into a blender and whizz for a few seconds. Melt the butter in a small saucepan over a lowish heat, then raise the temperature and bring the butter to a bubble. Leave the pan to one side for a minute to allow the milky residue to settle.
With the blender going, slowly pour a thin stream of butter through the lid. Continue adding the golden liquid until the milky sediment appears (discard it). Remove the lid, season the sauce and whizz for a few more seconds. Replace the lid and keep the hollandaise in a warm place (but NOT over direct heat) for up to 30 minutes.
Tip the warm vegetables into a large mixing bowl and add the gherkins and (optional) capers. Very, very gently stir in the sauce, using a soft plastic scraper. Serve as soon as possible.