If you are wondering what steaming hot dish to serve up at your firework party this year - think soup. Soup is one of the most versatile meals there is. It can be thick and chunky, or smooth and warming, and can be flavoured with fruits and spices from all over the world. But the best thing about soup is the ease with which it can be made - and from virtually anything. If you are prepared to make it from seasonal vegetables and a few herbs it can also be the cheapest way of feeding a large number of party guests on bonfire night.

Perhaps one of the most famous soups of all is the fictional stone soup created by a wandering soldier in post-war Eastern Europe, during a great famine when people jealously hoarded whatever food they could find.

The tale goes something like this . . .

The soldier had wandered into a village and been told there was nothing to eat. He said that wasn't a problem as he intended to cook himself a pot of stone soup which he was prepared to share with them all. With great ceremony he pulled an iron cauldron from his wagon, filled it with water and set it over a fire. He then pulled a very ordinary looking stone from his pocket and placed it into the pot. The villagers gathered around, watching the soldier stir the soup. The soldier licked his lips in anticipation, then said: "I do like a tasty stone soup, but of course stone soup with cabbage would be even better." Soon a villager approached holding a cabbage and it was added to the pot. "Great," said the soldier, who added that it would taste even better with a little salt beef as well. It wasn't long before a little salt beef was offered, then carrots, potatoes and mushrooms, until the most delicious cauldron of soup bubbled over the fire for all to share. The soldier was offered a great deal of money for his magic stone, but he refused to sell.

You don't need a magic stone to create a tasty soup, of course - just a few vegetables, stock and imagination, because soup is essentially a hunter-gatherer's food. The word soup originates from the Teutonic word suppa, which refers to a medieval dish of thick stew that's been poured on slices of bread called sop which soaked up the liquid. French onion soup, finished off by placing pieces of toast sprinkled with cheese into the soup, is an example of a modern soup that's served with bread sops.

Actually, French onion soup, with its delicious caramelised onions and melted cheese, makes an ideal party soup, though perhaps best suited to the adults if the broth has been made to the classic recipe which calls for white wine and cognac. But without much extra effort a choice of several soups could be offered at a firework party, along with several different types of bread - though hot garlic bread is probably the most suitable for November 5. A cream of tomato, or a rich vegetable soup to which a tin or two of baked beans have been added, are often popular soups for the younger members of the family. A garnish of pasta is often popular with the children too.

If you really want to push the boat out you could select soups that represent the four corners of the globe. These could include avgolemono, a Greek chicken soup flavoured with lemon and egg; borscht, a beetroot soup from Eastern Europe; cock-a-leekie, a leek and potato soup from Scotland; goulash, a meaty Hungarian soup spiced with paprika; lentil soup, from the Middle East and Mediterranean; minestrone, a glorious mix of vegetables popular in Italy; or mulligatawny, an Anglo-Indian soup spiced with curry powders.

The easiest soups to make - and probably the cheapest - are the purees made by cooking vegetables such as carrots, then liquidising them with a little of the cooking liquor to which other flavours, such as orange juice, fresh ginger or spices, have been added.

By adding chopped apple to vegetables such as pumpkin, squash or parsnips, which have been roasted to give a deeper flavour before they are liquidised, you can create a simply glorious soup. Then by garnishing your puree soups with crunchy bacon bits or croutons, and perhaps a swirl of cream, you can enhance the flavour further.

Vegetables such as cauliflowers or mushrooms make excellent soups too. These call for a milk base, but are just as easy to make. Coconut milk is another way of adding flavour to an autumn vegetable, and goes particularly well with pureed pumpkin or butternut squash. I was introduced to this combination by Sandy Helig, the owner of Eysham's deli Cornucopia, while we were discussing seasonal vegetables that could be cooked in the R-Oil I wrote about last week. Apparently, it's a firm favourite with her customers.

To make enough for four people you would need one medium-sized butternut squash, half a tin (200ml) of coconut milk, 400ml of water, half a dozen lime leaves, the juice of one lime, a piece of ginger the size of a walnut, a little oil, a clove of garlic, a pinch chilli powder, and salt and freshly ground black peppercorns to season.

To make up, peel, de-seed and chop the squash, brush with oil and bake in a medium oven until tender. Place the baked squash in a large saucepan with the water and coconut milk. Chop the ginger and garlic and add to the pot, along with the lime leaves and lime juice. Season, add the chilli powder and cook for about ten minutes. Remove the pan from the heat, allow the soup to cool a little (this will give the lime leaves time to infuse their flavour into the liquid), then remove the leaves and zap the rest through the liquidiser, adding a little extra water if the soup appears too thick.

You can buy fresh lime leaves from the Lung Wahm Chong Chinese supermarket at 41-42 Hythe Bridge Street, Oxford, and get all the seasonal vegetables you need for your soups from your local farmers' market or farm shop.