Preheat the oven to 400 degrees F.
Brown the lamb all over for 10 minutes in the oil in a Dutch oven or big ovenproof pot or dish.
Remove the lamb and put the carrot and onion in the pot.
Cook for 10 minutes, then add the garlic and herbs and cook for 2 minutes.
Stir in the flour and tomato paste, add salt and black pepper, and add the stock and wine.
Put the lamb back in the pan and bring to a simmer.
Cover with a lid or with foil and cook in the oven for 1½ to 2 hours or until the lamb is tender.
Take the meat out of the sauce and set it to one side.
Cover it loosely with foil.
Put the pan back on the heat and simmer the sauce for 15 minutes or until thick and glossy.
Sieve it into a jug, then serve it with the lamb.