Rinse the beans and put in a large pan
with 1 onion, 1 carrot and 1 celery stick,
all halved, 1 unpeeled garlic clove and the
bouquet garni. Cover with water, bring to
the boil, then reduce the heat and simmer
for about 30-45 mins, until the beans are
almost tender but holding their shape.
Meanwhile, chop the remaining onion,
carrots and celery stick. Peel and finely
chop the remaining garlic. Heat the
butter and oil in a large pan, add the
vegetables and gently fry for 10 mins
until lightly coloured.
Drain the beans, reserving the cooking
liquid. Fish out and discard the whole
vegetables and bouquet garni. Add the
beans to the pan of vegetables with the
tomatoes and sufficient reserved cooking
liquid to just cover them. Top up with
boiling water if necessary. Add plenty of
salt and pepper and bring to the boil.
Cover and simmer for about 30 mins
until the beans and vegetables are tender,
then scatter with parsley, to serve.