Preheat the oven to fan 160C/ conventional
180C/gas 4. Weigh the ham and calculate
the cooking time at 25 minutes per 500g.
Scatter the onion, ginger, thyme and cloves
over the base of a large, deep roasting tin.
Put the soaked ham on top and add water
to 3-5cm deep. Cover the whole ham and
tin with two or three layers of foil (making
a tent over the ham to allow the steam to
circulate), sealing the foil around the edges
of the tin. Bake for 1½ hours, then reduce
the oven to fan 140C/conventional
160C/gas 3 for the remaining 2 hours
40 minutes of the cooking time. When the
ham is cooked, remove it from the oven.
Leave to rest for 30 minutes.
Now make the glaze. Put the sugar and
100ml/3½⁄2fl oz water in a medium pan. Heat
gently until the sugar melts, add the fresh
ginger and simmer for 3-4 minutes. Add
the kumquats and cook for a few more
minutes, just until they soften. Scoop out
and reserve the kumquats, discard the
ginger and add the stem ginger strips.
Bring to the boil, then turn down the heat
and let the mixture bubble for 3-5 minutes
until thick and reduced by just under half.
Remove from the heat and set aside.
Line a clean roasting tin with foil and oil it.
Unwrap the ham and put it in the foil-lined
tin. Cut off the skin, leaving a layer of fat all
over. Using a sharp knife, score the fat into
a diamond criss-cross pattern. Turn up the
oven to fan 200C/conventional 220C/gas 7.
Rub ground ginger over ham, then brush
over all but a couple of spoonfuls of the glaze,
distributing stem ginger strips. Scatter over
kumquat slices, studding cloves through
some to secure. Drizzle over remaining
glaze. Roast for another 20 minutes or until
golden and sticky and kumquats start to
colour. Serve garnished with halved kumquats
and sprigs of bay leaves. If serving hot, allow
to rest for 15-20 minutes before carving.