Heat 4 tablespoons of oil in a large saucepan or deep casserole, and fry the onions and carrots until they begin to soften, about 5 minutes.
Remove the softened and oil-glossed vegetables to a bowl, and add the remaining oil to the pan. Put the flour into a large freezer bag along with salt and pepper, sage, and allspice; add the beef pieces to the bag, tossing in the flour, before searing the meat in the pan. Do this in batches, browning the meat a little and removing all of the beef to a large dish as you go.
When all the meat is browned and out of the pan, whisk or stir in the orange juice and stout and let it come to the boil. Add the water and then return the meat and vegetables to the pan. Stir in the orange zest and bay leaves, bring to the boil and then turn the stew down to a soft simmer. Cover and cook for 2 1/2 hours. This is best reheated 1 or 2 days after, but if you are serving the stew on the same day, then add another half hour to the cooking time just to make sure the meat is soft, mellow and tender.