Liver is polarizing; there aren't many people who kind-of like liver. You're either a lover or a hater, and if you're a lover there's no doubt you've had versions of this dish many times before. And if you're a hater, well, you're missing out. Liver and onions is a dish you can still find on many diner menus; the sweetness of the onions and the meatiness of the liver are a perfect combination. And adding some crisp fried potatoes and lovely thick cut bacon turn a humble lunch into a substantial supper.
Some people soak their liver in milk before cooking it. It's my opinion that if you get good quality fresh liver, that process is simply a waste of milk. Both the onions and the potatoes are cooked in leftover bacon fat and because of that, make sure you get very good quality bacon. If you can't locate good quality bacon that you trust, cook the bacon separately and cook the onions and potatoes in a few tablespoons of butter. Meals as simple as this are totally reliant on the quality of the ingredients that you use. It's especially important when cooking offal that you make the extra effort to get the best ingredients you can find.