Cut two eel fillets (skinned) into 15 pieces and place in a deep dish. Finely chop half a bunch of parsley, dill and chives, then mix with 8 cl Kümmel, four tablespoons of vinegar and six tablespoons of oil. Peel some horseradish and finely grate about 15–20 g to add to the herb marinade. Cut a red onion in half and slice into very thin rings. Pour the onion and herb marinade evenly over the sliced eel fillets, then leave covered in the refrigerator to absorb the flavour for at least two hours (preferably overnight). Serve the eel on 15 pumpernickel discs.