Cut the herring fillet and the herring / rollmops into small pieces. Cut the onions into fine rings with the bread machine and place in the vinegar sauce of the herring for about 30 minutes.
Mix the fish, the pickles, capers, onion rings with mustard and crème fraîche and slowly stir in the cream. The sauce shouldn`t get too thin. You can mix in a little vinegar water from the herring). Season with salt and pepper.
Cover and let the fish salad stand in the refrigerator for an hour.
Tip:
If you like leeks, you can cut a small stick into fine rings and mix in.