In a large casserole dish, gently dry the onions, peppers and carrots in a little oil until softened, then add the remaining stew ingredients and stir until combined. Add the beef and add water as required until just a little of the brisket is peeping out. Cover loosely and simmer for 5 – 6 hours until the brisket is tender – when you put a fork into it it should slide back out easily. Leave covered for 30 minutes to rest. You can light your barbecue and prepare your corn in this time.