I dip the liver in flour and fry it in olive oil before adding fried onions (softened and golden in colour), tomato puree, salt and pepperto taste plus water and simmer gently.
That in itself is perfection in my books but I'll sometimes add mushrooms to the onions while frying them. Bacon is OK as an addition but I prefer to omit it.
I'm happy to serve the liver with rice, cous cous or wholemeal chapattis.
It's such a cheap meal to prepare and, living in a household where I am the only liver enthusiast means I don't have to share it with anyone