Mix orange juice, balsamic vinegar, mustard and olive oil into a dressing, season with salt, pepper and Worcestershire sauce.
Chop the liver into small pieces, heat the butter fat, add the liver and fry briefly. Season to taste with salt and pepper. Mix the lamb`s lettuce with the dressing and divide on 4 plates. Place the hot liver around the salad and garnish with the orange fillets.
Tip: Do not add salt to the liver until it is done, otherwise it will harden.
Instead of chicken liver, you can also use veal liver.