Marco Pierre White's Pea and Ham Soup

Make a stock by placing the gammon into a large saucepan, along with the celery, carrot, onion, thyme, bay leaves, peppercorns and two large pinches of salt. Cover with cold water, put the lid on the pan and bring to the boil.

When boiling, immediately reduce the heat to a gentle simmer. After 20 minutes, use a slotted spoon to skim off the scum from the water's surface. Continue to simmer for about 11/2 hours, topping up with warm water if necessary. After two hours, turn off the heat.
Carefully remove the hot ham from the saucepan and place it on a carving board. Carve the joint while it is still hot and cut the slices into bite-sized pieces. These will later be used in the soup.

Sieve the stock, discarding the vegetables, peppercorns, thyme and bay leaves. Allow the liquid to cool before chilling it in the fridge.

Thaw the peas until semi-defrosted, and then liquidise them with the chilled stock.

Pass the pea and stock purée through a sieve.

In a saucepan, heat the sieved purée, but don't boil it or the liquid will lose its vibrant green colour. Season with salt to taste and stir in the butter for richness.

Place the pieces of ham into bowls and pour over the soup.