Smoked ham hock, potato, avocado and onion salad with mustard-seed dressing

For the ham hock, soak the ham in cold water, 30 minutes. Drain and place in a large heavy-based saucepan with the onion, carrots, celery, leek and garlic. Cover with the chicken stock or water and gently bring to a boil. Reduce the heat to low and skim the stock well. Add the white peppercorns, bay leaves, thyme and seasoning and allow to barely simmer, 2½ – 3 hours.

When the hock is ready, the skin covering it will peel away easily and the meat on the ham hock will come away from the bone without resistance. If the meat requires additional cooking, simply return to the heat and check again after a further 15 minutes. When the ham hock is ready, remove from heat and allow the hock to cool in the cooking stock.

When the ham hock is cold, lift it out of the stock. Remove the thick layer of skin surrounding it, then pick off the meat from the ham-hock bone into large bitesized pieces. A 1,5kg ham hock will yield approximately 400g meat. Pass the stock through a fine chinois (conical sieve) and reserve the stock for another use, such as soup or risotto.

For the dressing, place the egg yolks, mustard, vinegar and Worcestershire sauce in a bowl and whisk until pale and double in volume. Add the oil in a slow, steady stream so that the egg yolk absorbs the oil. Continue to whisk until all the oil has been incorporated. Season to taste with salt, pepper and a squeeze of lemon juice. If the dressing is too thick, thin it out with a dash of warm water. Add the wholegrain mustard, cover with cling film and refrigerate until ready to use.

To assemble, arrange the ham hock between 4 chilled plates, spoon the avocado purée into a piping bag and pipe small dots of avocado around the plate. Divide the potatoes and onions among the plates. Drizzle the mustard seed dressing over and around the ham hock. Arrange the salad leaves over the ham hock and drizzle with olive oil to serve, if desired.