1 Rinse herring thoroughly and cut off the fins and the tail fins. Rub inside and out with salt.
2 Place flour in a shallow dish. Dredge half of the herring in flour, tapping off excess.
3 Heat 4 tablespoons oil in a large non-stick pan over medium heat. Fry the coated herring until browned on each side, about 5 minutes per side.
4 Remove herring with a slotted spoon and let drain and cool. Pour off the oil from the pan and wipe clean. Dredge remaining 4 herring in flour. Heat oil in pan and fry remaining herring.
5 Combine the peppercorns, mustard seeds, juniper berries, bay leaves, broth and vinegar in a pot and bring to a boil.
6 Peel onions and cut into rings. Add to the vinegar mixture and return to a boil. Cover and cook over low heat until onions are tender, about 10 minutes. Allow to cool and season with salt.
7 Arrange the fried herrings in a rectangular mold of about 1.5 liters (approximately 1 1/2 quarts), pour the cooled broth over and let marinate for at least 1 day in the refrigerator.
8 Remove herring from the broth, drain and serve with the pickled onions. Serve with roasted potatoes or brown bread, if desired.