Wash liver, dab dry and turn in flour. Heat 2 tablespoons of oil in a frying pan and fry the liver in it for about 5 minutes on each side at medium heat. Season with salt and pepper.
Clean, wash and drain the salad. Apple wash, quarter and cut out core. Cut apple into slices and drizzle with lemon juice. Clean, wash and cut celery into pieces.
Peel and finely chop the onion. Mix with raisins, vinegar and honey and season with salt and pepper. Add the remaining oil and fold it in. Mix salad ingredients and vinaigrette. Arrange on a plate together with the liver.
Garnish as desired with a slice of apple and serve.