You haven't really given us enough information here. Is Hall & Woodhouse a restaurant? Or do you mean one of the pubs run by H&W brewery? If so, there are loads of them and having had a quick look online, they don't all seem to have the same menus.
The menus I looked at all seemed to have some kind of steak, so you could have that without the sauce. Or a salad without dressings. The one in Bath seemed to have a more specialised menu and has grilled fish dishes, the other one I looked at (Worlds End near Blandford) seemed to have a more general menu which might apply to other places too - it had steaks and roasts and baked salmon, also a moroccan vegetable dish which looked nice.
The trick with eating out is to ask for exactly what you want. A polite smile and the request "may I have that without . . . . " is usually enough. Restaurants are used to people having dietary requirements, allergies, etc. And if it doesn't arrive on your plate, you can't eat it by mistake!