Janssens Frestelse

I've three Swedish recipes coming up over the next few days, since I'm pretty sure you're getting sick of my endless riffing on Malaysian and Chinese things-with-rice. I've a soft spot for Scandinavian cuisine, which makes a lovely, hearty change when the weather starts to turn towards autumn. Swedish food is characterised by its use of dairy products, fish of all kinds, large game meats like reindeer, and preserved foods. You'll find relatively few vegetables in Scandinavian cookery; the long winters preclude much that is green and leafy.

This potato dish, flavoured with onions and anchovy (which ends up surprisingly mild and creamy), is a traditional part of the Swedish smorgasbord, a buffet where cold and hot foods are served up in several courses. I was lucky enough to try an authentic smorgasbord in a manor house in rural Lincolnshire (I've lived, I tell you) when I was a teenager. The place was run by a Swedish couple, and offered a glorious and fresh spread of cold, cured or smoked fish (no lutefisk as I recall, but if you're putting your own together, lutefisk would be very appropriate) as an opener. Sliced meats, cheese and a cucumber salad came next, followed by a third, hot course of those ubiquitous meatballs, stewed red cabbage, a venison casserole and a lovely, savoury gratin - Janssons frestelse. The restaurant is long gone now, but visits I've made later to Scandinavia have confirmed that what we ate that night was authentic and very well prepared. (The dish pops up in other countries in the region; I've eaten it as Janssonin kiusaus in Finland, and very good it was too.)

Although English recipes tend to use anchovies, spiced and preserved sprats (ansjovis in Swedish - you can see where the confusion came about) are usually used in this dish in Sweden. You can't find these fat, oily little preserved fish for love or money in the UK, so a really good preserved anchovy is your best bet. Sainsbury's do some absolutely glorious (and rather expensive) large anchovies preserved in oil with chillies in their world food section. These anchovies are very mild (you can eat them unaccompanied with your fingers, and they're not too salty, just very, very tasty), and work very well here. Otherwise, any good French brand will do. It's important that your anchovies are good quality ones, which will tend to have a softer, less fierce flavour - I know anchovy-haters who have been converted by this dish.

Stop press - I have been informed by a reader that Swedish ansjovis are, in fact, available at Ikea, of all places. Buy some next time you pop in for some shelving. Their Swedish meatballs are also fantastic.

I chose King Edward potatoes for their flavour and their ability to absorb the cream. This isn't totally authentic - you're more likely to find a more waxy potato in this dish in Sweden (I've even had it with new potatoes). I personally find that a floury potato works better for my own tastes, but you should feel free to experiment - if you want a waxier potato in the UK, Vivaldi would be excellent, as would Kestrel.

To make Janssons frestelse as a side dish for four to five people, you'll need:

4 large potatoes (I used King Edwards)
1 large sweet onion
10 anchovies preserved in oil
1 pint double cream
½ pint milk (you may need a little less)
1 handful breadcrumbs
2 tablespoons grated parmesan
2 large tablespoons salted butter

Preheat the oven to 225° C (475° F). Slice the potatoes thinly and make a layer of slices in a fish-scale pattern in a 2 pint gratin dish. (Some recipes call for potatoes cut in matchsticks; others for grated potatoes; others for thin slices. It doesn't make any difference to the flavour, and you're likely to find thin slices more manageable.) Slice the onion thinly and place a layer of slices on top of the potatoes, seasoning with pepper as you layer. You won't need any salt; there is plenty of that in the anchovies. Lay out half the anchovies on top of the onions. Cover with a layer of potatoes, a layer of onions, more anchovies and a final potato layer. Pour over the cream, and sprinkle the top with the breadcrumbs mixed with the (totally inauthentic, so leave if out if you like) parmesan. Dot the surface with softened butter.

Bake in the oven, uncovered, for 30 minutes. The cream will have been absorbed into the potatoes and some will also have evaporated - top the dish up with some milk. Continue to cook for another 15 minutes, until the potatoes are tender and the breadcrumbs are crisp.