Tip the beef into a bowl, then pour over
the balsamic vinegar. Mix well, then leave
to marinate in the fridge for 1 hr.
Heat oven to 180C/fan 160C/gas 6. Put
the beef stock, garlic, onion, carrots and
herbs into a casserole dish with the beef
and its marinade. Mix everything together,
cover, then place in the oven. Cook for
2½ hrs until the beef is really tender, then
leave to cool slightly.
Tip the beef into a colander with a bowl
underneath to catch the juices. Tip the liquid
back into the casserole then, on the hob,
bring to the boil until it starts to become a
syrupy gravy. If you prefer your gravy thicker,
add the cornflour and simmer, stirring, for
1 min more. Return the beef to the sauce and serve. Can be frozen for up to 1 month.