First, soak the gammon in cold water for 2 hours, to help remove some of the saltiness.
Put all the sauce ingredients except the butter into a small saucepan, and place over a moderate heat for about 5 minutes, whisking until combined. Take off the heat and whisk in the butter until it has emulsified into the sauce. Set aside.
In a frying pan, heat half the oil over a high heat. Once the pan is smoking hot, add the gammon chops and fry for 2 minutes on each side. Remove from the pan and set aside.
Wash the pan, return to the heat, and add remaining oil before adding the pineapple. Fry on each side for a couple of minutes.
Place one round of pineapple on top of each gammon steak. Pour over the glaze, serve immediately the traditional British way, with chips! Or alternatively with sushi rice or plain rice.
Mixed Mushrooms in Oyster Sauce