Summer soup

¼ cup olive oil
2 small onions, chopped into ½-inch dice
2 large potatoes, about 1 pound in total, chopped into ½-inch dice (about 3 cups)
8 ounces zucchini, chopped into ½-inch dice (about 2 cups)
leaves stripped from a few sprigs of fresh thyme
4 cups hot vegetable or chicken stock
1 head of romaine, finely shredded
handful each of fresh mint and flat-leaf parsley, leaves chopped

If you decide to purée the soup, mix in some heavy cream after blending, to add richness and to give a silky texture.

Heat a large pot with the oil and add the onions and potatoes. Cook over medium heat for 4–5 minutes, stirring frequently. Add the zucchini, thyme leaves, and some salt and pepper and cook for a couple of minutes longer.
Pour in the stock and bring to a boil. Lower the heat and simmer for 5 minutes. Taste and adjust the seasoning. Add the lettuce and remove from the heat as soon as the lettuce has wilted. Scatter half of the chopped herbs over the soup. Ladle into warm bowls and garnish with the remaining chopped herbs.