Cut the courgettes – wash them by all means if you want, but don’t bother to peel them – into 5mm / one-eighth of an inch rings, and then finely dice them. Put them into a pan with the lemon zest and oil, stir to coat, then cook on a gentle heat for about 5 minutes, stirring occasionally, until they’ve slightly softened.
Stir in the turmeric and pour in the stock and lemon juice and then drop in the rice. And for the stock here, as usual I make up some bouillon concentrate with water; you could use vegetable stock if you prefer, but I love the mellow goldenness you get from chicken.
Cook, uncovered, for 10-20 minutes, or just until the courgettes and rice are tender. Taste for seasoning.
Leave to cool slightly before serving so that you eat the soup warm rather than hot.