Clean the truffle with
a small brush, to remove all the dirt, then cut it into small batons.
Surround the meat with the truffle and the sliced garlic cloves.
Clean the onion, celery, carrot and parsley and finely chop them all
together with the bacon. Let the chopped mixture simmer in a saucepan
with hot oil, then carefully place the piece of meat on top, letting
it brown well on all sides. Cover it with the hot stock and continue
to cook at a low heat for about an hour and a half, turning the
roasted meat frequently and mixing the cooking juices from the bottom
of the pan by adding more hot stock.
When the cooking
time has finished, carve the meat into slices and arrange them on an
ovenproof plate. Strain the sauce through a colander incorporating
the butter and then putting it back on the heat, let it thicken for a
few minutes. Stirring carefully. Afterwards pour it over the meat and
put it in a hot oven at 180°C/350°F for a quarter of an hour. Take
it straight away to the table, nice and hot.