How to make Swedish potato and fish gratin

It's been a chilly week across Sweden. This dish (called Janssons frestelse in Swedish) is guaranteed to warm you up. Food writer John Duxbury shares his recipe with The Local.

How to make Swedish potato and fish gratin
Traditional Swedish potato and fish casserole. Photo: Malin Hoelstad/SvD/SCANPIX/TT

Quick overview

Makes: 4 portions

Time needed: 70 minutes


450 g (1lb) potatoes (preferably a floury type such as King Edward)

1 onion

125 g (4½ oz) tin of spice-cured sprats (look for ‘skarpsill’ or ‘ansjovis’)

150 ml (3/4 cup) whipping cream (light cream)

4 tbsp milk

1 tbsp white breadcrumbs

1 tbsp butter

1 tbsp salt and pepper

The dish was introduced into the Swedish cuisine in the 1940s. Photo: Janerik Henriksson/TT


1. Preheat the oven to 230C.

2. Peel the potatoes and then cut them into juliennes or thin strips (you could use a julienne disc on a food processor to do this but the size isn't critical).  

3. Peel the onion and cut into julienne strips.

4. Fry the onion in butter until it’s softened without browning.

5. Drain the spiced brine from the ‘ansjovis’ tin into a jug. Add the cream and milk.

6. Cut the ‘ansjovis’ into 1cm lengths.

7. Lightly grease an ovenproof baking dish.

8. Cover the bottom of the dish with a third of the potatoes, then add half the ‘ansjovis’ pieces.

9. Add another third of the potatoes and top with the remaining ‘ansjovis’ pieces.

10. Add the remaining third of the potatoes, then season with pepper (you probably don’t need any salt as the ‘ansjovis’ are very salty).

11. Flatten the surface, then pour the cream, milk, and spiced brine over it.  

12. Sprinkle the breadcrumbs over the dish and dot the surface with butter.

13. Bake for about an hour until golden brown.

Serving suggestions

Wait until after your dinner guests have tasted the dish to tell them that it’s made with sprats! Serve hot, with bread (knäckebröd), cheese, and salad or warm as part of a smorgasbord.

Recipe courtesy of John Duxbury, Editor and Founder of Swedish Food

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The three tasty treats that make spring in Sweden a forager’s dream

Although parts of Sweden are still under snow at this time of year, spring is in full swing here in Skåne in the south of Sweden. Here are The Local's top tips for what you can forage in the great outdoors this season.

The three tasty treats that make spring in Sweden a forager's dream

You might already have your go-to svampställe where you forage mushrooms in autumn, but mushrooms aren’t the only thing you can forage in Sweden. The season for fruits and berries hasn’t quite started yet, but there is a wide range of produce on offer if you know where to look.

Obviously, all of these plants grow in the wild, meaning it’s a good idea to wash them thoroughly before you use them. You should also be respectful of nature and of other would-be foragers when you’re out foraging, and make sure not to take more than your fair share to ensure there’s enough for everyone.

As with all foraged foods, only pick and eat what you know. The plants in this guide do not look similar to any poisonous plants, but it’s always better to be safe than sorry – or ask someone who knows for help.

Additionally, avoid foraging plants close to the roadside or in other areas which could be more polluted. If you haven’t tried any of these plants before, start in small doses to make sure you don’t react negatively to them.

Wild garlic plants in a park in Alnarpsparken, Skåne. Photo: Johan Nilsson/TT

Wild garlic

These pungent green leaves are just starting to pop up in shady wooded areas, and may even hang around as late as June in some areas. Wild garlic or ramsons, known as ramslök in Swedish, smell strongly of garlic and have wide, flat, pointed leaves which grow low to the ground.

The whole plant is edible: leaves, flowers and the bulbs underground – although try not to harvest too many bulbs or the plants won’t grow back next year.

The leaves have a very strong garlic taste which gets weaker once cooked. Common recipes for wild garlic include pesto and herb butter or herbed oil, but it can generally be used instead of traditional garlic in most recipes. If you’re cooking wild garlic, add it to the dish at the last possible moment so it still retains some flavour.

You can also preserve the flower buds and seed capsules as wild garlic capers, known as ramslökskapris in Swedish, which will then keep for up to a year.

Stinging nettles. Wear gloves when harvesting these to protect yourself from their needles. Photo: Johan Nilsson/TT

Stinging nettles

Brännässlor or stinging nettles need to be cooked before eating to remove their sting, although blanching them for a couple of seconds in boiling water should do the trick. For the same reason, make sure you wear good gardening gloves when you pick them so you don’t get stung.

Nettles often grow in the same conditions as wild garlic – shady woodlands, and are often regarded as weeds.

The younger leaves are best – they can get stringy and tough as they get older.

A very traditional use for brännässlor in Sweden is nässelsoppa, a bright green soup made from blanched nettles, often topped with a boiled or poached egg.

Some Swedes may also remember eating stuvade nässlor with salmon around Easter, where the nettles are cooked with cream, butter and milk. If you can’t get hold of nettles, they can be replaced with spinach for a similar result.

You can also dry nettles and use them to make tea, or use blanched nettles to make nettle pesto.

Kirskål or ground elder, another popular foraged green for this time of year.
Photo: Jessica Gow/TT

Ground elder

Ground elder is known as kirskål in Swedish, and can be used much in the same way as spinach. It also grows in shady areas, and is an invasive species, meaning that you shouldn’t be too worried about foraging too much of it (you might even find some in your garden!).

It is quite common in parks and old gardens, but can also be found in wooded areas. The stems and older leaves can be bitter, so try to focus on foraging the tender, younger leaves.

Ground elder has been cultivated in Sweden since at least 500BC, and has been historically used as a medicinal herb and as a vegetable. This is one of the reasons it can be found in old gardens near Swedish castles or country homes, as it was grown for use in cooking.

Kirskål is available from March to September, although it is best eaten earlier in the season.

As mentioned, ground elder can replace spinach in many recipes – you could also use it for pesto, in a quiche or salad, or to make ground elder soup.