In a frying pan melt a little dripping and fry the onion rings over a medium heat until they’re nicely tinged with brown and starting to caramelise all round the edges.
You can also watch how to chop onions in our Cookery School Video on the right. Now remove them to a plate, add a little more dripping to the pan if you need to and brown the meat over a fairly high heat. This browning (on both sides) will help the flavour. Next take the shallow gratin dish or casserole, arrange a layer of onion in it, place the steak on top and season well.
Add another layer of onion, pour in the Guinness, cover closely with either a lid or a double sheet of foil and cook near the top of the oven for 2½ - 3 hours, or until the steak is tender. This goes very well with some creamed potatoes – and with the oven on for that long, you might contemplate cooking another casserole at the same time.