Kashubian Herring in Tomato–Onion Sauce Recipe
Kashubian herring is a popular Polish festive and party appetizer. Herring fillets are combined with plenty of onion and a sweet-and-sour tomato sauce with raisins. It’s a bit like marinated fish in sweet-and-sour sauce known from other cuisines, but in a distinctly Polish, herring-based version.
This Kashubian-style herring combines the saltiness of fish with a rich tomato–onion sauce and sweet raisins, creating a layered sweet-and-sour flavor that’s iconic on Polish festive tables.
Chef's tips
Let the sauce cool completely before combining it with the fish to keep the herring firm. Prepare the dish at least a day in advance – the flavor improves significantly after resting in the fridge.
How to serve
Serve well chilled, with dark rye or sourdough bread and a few slices of pickled cucumber. It also works well as part of a larger selection of marinated fish and salads.
Ingredients
- herring fillets a'la matjes in oil or salted if salted, they need to be soaked - 500 g
- onion medium - 3 pieces
- tomato paste - 3 tablespoons
- passata or carton tomatoes - 200 ml
- oil - 4 tablespoons
- vinegar - 2 tablespoons
- sugar you can use less or more to taste - 2 tablespoons
- raisins - 3 tablespoons
- bay leaf - 2 pieces
- allspice whole berries - 4 grains
- pepper to taste
Preparation
- If using salted herring, rinse off the excess salt, then cover with cold water and soak for 2–3 hours, changing the water every hour. Taste a piece at the end – if it is still very salty, soak a bit longer.
- Pat the herring dry with paper towels and cut into pieces about 2–3 cm wide.
- Peel the onions and slice into thin half-moons.
- Heat 3 tablespoons of oil in a frying pan. Add the onion and fry for 8–10 minutes over medium heat, stirring often, until softened and lightly translucent. Do not let it brown deeply.
- Add the bay leaves, allspice, and tomato paste and fry for 1–2 minutes, stirring so the paste toasts lightly.
- Pour in the passata, add the sugar, vinegar and raisins. Stir and simmer over low heat for 5–7 minutes until the sauce thickens slightly.
- Season the sauce with pepper. Taste and, if needed, add more sugar or vinegar to achieve a pleasant sweet-and-sour balance.
- Remove the sauce from the heat and leave to cool completely. This is important – do not pour hot sauce over the herring.
- In a glass or ceramic dish, layer the herring pieces and the tomato–onion sauce, starting and finishing with a layer of sauce.
- Cover the dish and refrigerate for at least 12 hours, preferably a full day, so the flavors can meld.
Storage
Śledzie po kaszubsku przechowuj w lodówce w zamkniętym pojemniku, całkowicie przykryte sosem. Z czasem smak staje się jeszcze lepszy.
