Scatter the rice into a deep baking tray, along with the carrots, cauliflower florets, green beans, sweetcorn and cashews.
Pour the coconut milk into a jug, along with 200ml cold water. Whisk in the curry paste, turmeric, cumin and chilli flakes until combined. Pour the spiced coconut milk mix over the rice and gently stir through to ensure all of the rice is coated.
Loosely cover the baking tray with foil, then bake in the oven for 45–50 minutes until the coconut milk has been absorbed by the rice and the vegetables have softened.
Carefully remove the tray from the oven and remove the foil. Scatter over the spring onions and coriander, then season with sea salt and lemon juice. Serve hot with wedges of lemon.