Summer Pistou

1. Heat the oil in a large pan and fry the leeks and courgette for 5 mins to soften. Pour in the stock, add three-quarters of the haricot beans with the green beans, half the tomatoes, and simmer for 5-8 mins until the vegetables are tender.
   5 minutes5–8 minutes
2. Meanwhile, blitz the remaining beans and tomatoes, the garlic and basil in a food processor (or in a bowl with a stick blender) until smooth, then stir in the Parmesan. Stir the sauce into the soup, cook for 1 min, then ladle half into bowls or pour into a flask for a packed lunch. Chill the remainder. Will keep for a couple of days.
   1 minute

Cooking notes

Most vegetable dishes scale linearly, but be mindful of pan crowding — vegetables that should brown will steam instead if packed too tightly.

For volume-to-weight conversions of any ingredient — flour, sugar, butter, salts — use the ingredient converter. To translate the recipe's oven temperature between °C, °F and gas mark, see the temperature converter.

When you scale this recipe up or down, remember that cooking time does not scale linearly. A doubled cake takes longer, but not twice as long; a doubled soup takes roughly twice as long. The cooking-time guide gives sensible starting estimates by dish geometry.