Season the topside roast with salt and pepper and place into a shallow baking dish or large resealable bag. Combine the Merlot and balsamic vinegar; pour in with the beef. Seal or cover, and marinate in the refrigerator for at least 2 hours.
Preheat the oven to 150C.
Arrange onion rings in the bottom of a baking tray. Season with garlic, thyme and rosemary. Pour the marinade into the bottom of the tray along with the beef stock and stewed tomatoes and lay the roast on top of the onions so they form a roasting rack. Cover tightly with a lid or aluminium foil.
Bake for 3 hours in the preheated oven, then peel back the aluminium foil and add carrots and celery to the pan. Cover again and continue roasting for an additional 1 to 2 hours, or until the brisket can be pulled apart with a fork.
. Nice easy recipe, thanks. Unfortunately my beef did not turn out meltingly tender despite following your times and ingredients; not too tough but not that tender. Smelt delicious though and made gorgeous gravy from the juices with a little extra flour and bisto gravy granules. The veges cooked with the beef needed a little longer in the oven on their own on a baking tray to dry out. Served with extra green veg and mashed potato, a delicious autumn/ winter Sunday roast. - 20 Apr 2013
Turned out well. Only used 1.5kg piece and cooked for about 4hours and it was melt in your mouth. Just need to make sure the meat feels like it's going to pull a part. Served with polenta and spinach. Lovely. - 03 May 2014