Put the 600 ml of pineapple juice and the gammon into the pressure cook and bring to the boil.
Put on the lid and bring up to pressure. Cook for 1 hour and allow to cool by itself.
Roasting Sauce: Mix all the other ingredients together with a hand blender. Pre-heat oven to 180°C.
Take the gammon from the pressure cooker (discard the cooking liquid) and put into a roasting tin.
Remove the skin and most of the fat, but leave a thin layer.
Pour the sauce over all the joint then pop it into the oven for 20 minutes until nicely browned all over.
Serve with the sauce poured over and the vegetables of your choice. Enjoy!