Instructions: Soak the gammon in plenty of cold water for 24 hours.

Take a large piece of foil twice the size of the large roasting tin.

Line the tin with it letting the foil overlap. Lift the gammon on top and spread with black treacle.

Sprinkle with crushed peppercorns and loosely fold the foil over the top.

Slide the roasting tin on to the floor of the simmering oven.

Cook overnight for about 14 hours (maybe longer in a slow older aga).

Check first thing in the morning.

Open the foil pierce the gammon with a skewer in the thickest part and if the skewer goes in easily and the juices that flow out are clear it is done.

If the centre feels firm and the juices are pink cook for longer.

Or you can test the meat with a meat thermometer.

Remove the foil throw away the salty juices and peel off the skin of the gammon when cool enough to handle. Score the fat diagonally with a sharp knife and stand the gammon on a new piece of foil in the roasting tin.

Sprinkle with mustard powder and demerara sugar.

Slide on the lowest set of runners in the roasting oven.

Roast until brown about 20 minutes serve hot or allow to cool.

If serving cold chill in the fridge for 12 hours or so before carving and serving.

Choose smoked or unsmoked gammon on or of the bone whichever appeals to you most. Once gammon is cooked it is called ham (confusing!). Cooking the gammon overnight means that the aga is free during the day to do other cooking. In my aga the gammon is tender after 13 hour so I start cooking it at about 8.30 pm after Ive taken whatever is in the simmering oven out for supper. The gammon is cooked by about 9.30 the next momrng and just needs skinning and browning. It is sensible to use a meat thermometer to check when the ham is done.

Serves 14

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