Peel the onion and the clove of garlic. Chop the peppers, tomatoes and zucchini very finely, the finer the better.
The vegetables in a pan in oil, I like to use the oil of the pickled tomatoes, roast them until dark, then deglaze with wine and vinegar. Add the sugar, coarsely chopped thyme and rosemary as well as the pepper and bay leaves. Cover the stock and bring to the boil, then let it cool down.
Layer the herring in a clay pot, pour a little brew over each layer and let it mature in the refrigerator for two days.