Heat oven to 180C/fan 160C/gas 4.
Remove the tough central stalk from the
cabbage leaves. Bring a large pan of salted
water to the boil, add the cabbage, then cook
for just 1-2 mins until the leaves are starting
to wilt. Drain and refresh under cold running
water. Drain well, then pat dry with a tea towel.
Heat the oil in a pan, add the onion, then
fry for 5 mins until slightly browned. Add
the rosemary and celery, then cook for 8 mins
more. Stir in the rice, then cook for a min or
so until the grains are glistening. Remove
from the heat, stir in the chestnuts and
cranberries, then season.
Spoon a little stuffing onto a cabbage
leaf, roll up and fold in the sides to enclose
the filling. Put in a single layer in a large,
oiled, shallow ovenproof dish with the join
underneath. Fill the remaining leaves in the
same way. Mix the stock, vinegar and honey,
then pour over the cabbage. Cover the dish
tightly with foil, bake for 1 hr, uncover, then
cook for a further 15 mins.