Salt and pepper the meat and fry in hot oil on all sides and remove. Fry the garlic, onions and carrots. Deglaze with beer and add tomato paste. Return the meat to the roaster and add the vinegar, sugar, bay leaf, salt and plenty of pepper. Bring to the boil and cover and simmer on a low flame for 2 hours.
Take the roast out of the pot, pass the stock through a sieve and bind with a sauce thickener. Season again with salt and pepper.