Taking inspiration from across Europe, Diana Henry creates soups that are as comforting as ever – but surprising, too. Photographs by Haarala Hamilton. Food styling by Valerie Berry

It was 29 degrees in Kraków, too hot for anything that required effort, so I took a novel to the milk bar near the hotel. Milk bars are Poland’s state-subsidised cafés – they really blossomed in the communist years – where you can eat reasonably priced Polish food. Despite the heat I ordered pierogi, the stuffed dumplings for which the country is famous.

Milk bars, certainly in communist times, were supposed to be a kind of leveller, and indeed the customers were a mixed bag: a rather grand lady in black drinking cold fruit tea; a lone middleaged man who looked as if his wife had just left him; and a family – mum, dad and children – who had clearly had enough of holidays. The family ordered soup but not a cold one, a hot one. They leaned over their bowls breathing in the steam, as if the soup was some kind of elixir. I’m not sure it mattered what it was made of as long as it was Polish.

Soups – a mix of stock and vegetables – are usually good for you, but you don’t eat them to get your five a day. You eat them because they ground you. Soup seemed more important in Poland than in most countries I’ve visited. According to Polish-british food writer Ren Behan, you rarely have a meal there without it. Soups are at the core of Polish home cooking, reflect its history and honour its vegetables and foraged foods.

When I came home, I did some reading about soups from Central and Eastern Europe: pots thickened with a roux, as in Hungary (another country where soups rule), and the sour soups of Romania. Further west, Austrians love soups both thick and brothy, and serve them with a multitude of adornments. Here, most people shudder when they hear the word ‘dumpling’, but in Central and Eastern Europe, as well as Germany, they’re legion. Dumplings can be as big as tennis balls or as small as drops of batter flicked from a teaspoon into simmering broth.

In her book on Romanian cooking, Carpathia, Irina Georgescu divides the soups there into two categories, both sour. Borș is the name of a soup type and also an ingredient. I have some borș fermenting right now. It’s made of wheat bran and polenta, sometimes with bay leaves and parsley, and is added to stock, though a mixture of vinegar, water and a little bit of sugar infused with parsley is an OK substitute. The other group is known as ciorbă. In these the sourness comes from tart fruit, vinegar or the brine from fermented cucumbers. Some are glorious, thick with beans and smoky sausage, the flavour lifted with quick-pickled onions.

There are two smells that make a house feel like a home and not just somewhere to live: the smell of stock and the smell of braises. We have so much choice these days, using ingredients from all over the world. Sometimes their role is to surprise with big flavours – we go crazy for the unfamiliar, tubs of gochujang and different types of harissa – and we often want quick gratification, like griddled chicken thighs with gochujang mayo and crispy coleslaw. But the slow cooking required for stock and casseroles creates layers of flavour, at the same time subtle and deep.

I fear for the future of soup. I’m never offered it in anyone’s house and my children don’t like it, but it’s a respectful way to cook. We get the most out of bones that might otherwise be discarded and use simple vegetables and pulses. No waste, healthy, inexpensive – that’s surely how we should be cooking. We don’t have to stick to our own traditions; we can make cold-weather soups from elsewhere in Europe, soups that use ingredients – root vegetables, cabbage, barley and mushrooms – found on our doorstep but which, through the use of paprika, dill, pickle juice, smoked ingredients, caraway seeds and sour cream, are also surprising.