3 tablespoons olive oil
knob of butter
2 onions, thinly sliced
400 grams floury potatoes (eg Agria), peeled and diced
500 grams firm zucchini, roughly chopped
400 grams fresh or frozen corn kernels
2 teaspoons ground cumin
2 cloves garlic, crushed
5 cups chicken or vegetable stock
½ cup basil
thick plain yoghurt
extra basil leaves
Heat the olive oil and butter in a large saucepan and add the onions and potatoes with a good pinch of salt. Cover and cook for 10 minutes, stirring occasionally. Add the zucchini, corn, cumin and the garlic and cook for 2 minutes. Add the stock, season and bring to the boil. Reduce the heat and simmer for 10 minutes or until the potatoes and corn are tender. Set aside to cool a little.
Transfer one third of the soup and all of the basil to a food processor and blend until smooth then tip back into the saucepan.
To serve: Reheat the soup and season if needed. Ladle into warm bowls and top with a spoonful of yoghurt, extra basil and a drizzle of olive oil.
Cook’s tip: If using fresh sweet corn, you will need 3-4 large cobs. Remove the husk and silks and put the flat end of the sweet corn on a cutting board. Use a sharp knife to cut off the kernels.