If ever you find yourself in Hakaniemi market in Helsinki at lunchtime you will do well to join the local shoppers in a bowl of fish soup. If there are no tables left, then perch on a stool at one of the indoor market's long counters, where you will be jostled by shoppers laden with bags of smoked salmon and crispbreads the size of steering wheels. The colour of a house brick, or ivory-hued and topped with a large sprig of dill, these soups are made in the market in kitchens as small as abroom cupboard. The best of these in a week's worth of eating was pale and mild – a beautiful bowl of salmon, swede and leek, its creamy depths spiked with lemon and tomato cubes.
The most welcome of the soups was based on the Finnish salmon-and-potato broth lohikeitto, but had seen a bit of not-too-outlandish tinkering in the style of cauliflower and swede. There were a couple of scallops in there, too, possibly as much by accident as design. The bowls here are deep and generously filled, and come with slices of rye bread as sweet as gingerbread and a little of dish of butter scattered with coarse flakes of sea salt.
Market food is rarely disappointing, but here it is as good as I have ever tasted it, sold side by side with stalls offering every cure of salmon there is, from beetroot to lemon and pink peppercorn and the ever-popular gravadlax. You eat to the piercing whine of the meat saw from the adjacent butcher's stall from where you can pick up your marinated reindeer steaks. There are salted fish and cured herrings, too; ceramic dishes of Jansson's temptation (anchovy and potato gratin) and fishcakes the size of a ball of buffalo mozzarella. Yes, there is raw fish, though not as diverse a selection as you might wish for, but sustainability is very much the word here.
If soup doesn't float your boat, you could lunch on half-moon discs of rye crispbread layered with smoked halibut or a slice of wild-mushroom tart made with the cepes that are piled high on stalls aside lingonberries and rosy apples smaller than a golf ball. (At the grand Café Kamp they sometimes have deep bowls of cep soup with rosemary)
Potatoes are a recurring ingredient in Finnish fish soups and they successfully saw off the cold autumn wind that whistled through my thermals throughout my stay. You see whole stalls of them proudly labelled Nicola, Siikli and Van Gogh. These local varieties are small and waxy and sit happily without turning to slurry in your soup. Any of our small, yellow-fleshed potatoes will work.
Another day, I came across a fish soup so different I could have been in another country. Tomato-based and broth-like, it came with Finnish pike-perch, green olives, mushrooms, and (something of a revelation to this cook) sliced gherkins – the sassiest addition I have ever had to a fish soup. Any associations with the Med were slashed with the inclusion of the ever-present chopped dill (it is their parsley) and a last-minute curl of soured cream. The effect was clean-tasting and piquant. In trendier places fish soup isn't overlooked either, it will just come in a (very) much smaller portion and with adegree or two more elegance. Either way, it's a bowl worth the trip.
SALMON AND DILL SOUP
This is not the classic lohikeitto, but the delicious interpretation I ate in the market. Serves 4 to 6.
onion 1 medium to large
leek 1
butter 50g
cauliflower 500g
waxy potatoes 750g
swede 350g
water 1.25 litres
tomatoes 2 medium-sized
salmon fillet 600g
cream 100ml
lemon juice to taste
dill a small bunch
buttered rye bread to serve
Peel the onion and roughly chop it. Shred and thoroughly rinse the leek. Melt the butter in a deep, heavy-based pan and add the onion and leek. Let them cook over alow-to-moderate heat, stirring regularly, so they do not colour. They should be soft enough to crush between your finger and thumb, so take your time over this.
Bring a pan of water to the boil. Break the cauliflower into large florets and cook them in the boiling water until just tender. They will get a little more cooking when they are added to the soup. Drain and set aside.
Peel and roughly dice the potatoes and swede. Add them to the onions and continue cooking over a low-to-moderate heat for 10 minutes, stirring regularly. Pour in the water, bring to the boil and lightly salt. Turn the heat down to a simmer and partially cover with a lid. Chop the tomatoes and add them to the soup, followed a few minutes later by the cauliflower.
When the swede and potatoes are fully tender, cut the salmon into large pieces and lower into the soup. Season with pepper and let the salmon cook for about 5 minutes until it is just cooked. Pour in the cream and mix in gently (you don't want the salmon to break up). Stir in a little lemon juice to taste. Chop a couple of tablespoons of dill and stir in, reserving some nice sprigs for the top. Ladle into bowls and serve with rye bread.
TOMATO FISH BROTH
Finely slice the fennel and mushrooms and add to the pan. Cook for a few minutes until the fennel has started to soften a little. Pour in the water or stock and bring to the boil. Turn down the heat and simmer for 20 minutes, adding salt and black pepper.
Slice the gherkins, stone and halve the olives, chop the parsley and dill and set aside. Lower the fish into the stock and cook for 3 or 4 minutes until the fish is just opaque. Stir the gherkins, olives, parsley and dill into the soup. Correct the seasoning and, if you wish, add a little of the liquid from the gherkin jar. Ladle into warm bowls and add a spoonful of soured cream to each.
Email Nigel at nigel.slater@observer.co.uk or visit theguardian.com/profile/nigelslater for all his recipes in one place
