1. Put your ham hocks in a large pan with your stock ingredients. Cover with cold water and warm on a high heat until you bring it to the boil.
Reduce the heat and simmer for 2 hours or until the meat falls away from the bone. Leave to cool in the pan.
2. Grease a 1 litre mould or loaf tin with a little oil, then line with clingfilm. Remove the hocks, then strain the stock through a sieve into a pan and set to one side.
3. Shred the ham into bite-sized pieces and mix with the parsley and mustard. Press the mixture into your already prepared mould.
4. Bring the stock you set to one side to the boil and reduce by half. Remove from the heat. Meanwhile, soak the gelatine in cold water for 5 minutes to soften. Remove from the water and squeeze out any excess liquid. Add to your hot stock and give it a thorough stir.
5. Pour enough of the stock over the ham to cover it. Tap the mould on your work surface to remove any air pockets, then cover with clingfilm. Chill for at least 4 hours.
6. To serve remove from the mould and carve into chunky slices.