Make home-cooked liver and onions by sauteing 1 diced onion in 3 tablespoons of butter until it softens, and then add 2 teaspoons of white sugar. Once the onion caramelizes, remove it from the skillet. Dip 1 pound of sliced calf livers in melted butter and flour before cooking them for 1 1/2 minutes on each side. Season the livers with salt and pepper before serving them with the caramelized onions.
To make another recipe, liver with onions and vinegar, trim 1 pound of calf livers, removing any membranes or veins, and cut them into thin 1/4-inch wide slices. Dip the liver slices in a mixture of flour, salt and pepper, and set them aside. Saute 2 sliced Spanish mushrooms in 2 to 4 tablespoons of butter for 15 minutes, and toss them with 1 tablespoon of vinegar, and add salt and pepper to taste.
Cook the liver slices in 2 to 4 tablespoons of clarified butter at high heat for 30 seconds on each side, and then add the onions to the liver slices, stirring until both ingredients are heated through and the liver is no longer raw in the center. Serve the liver and onions topped with 2 tablespoons of chopped fresh parsley.