Great curry to use up the pumpkin
First, soak the cashews and melon seeds in boiling water while you prepare the pumpkin. Chop into 2.5cm/1 inch cubes.
Preheat the oven to 200C/Gas Mark 6.
Put the pumpkin on a baking tray then drizzle with olive oil and season well with salt and pepper. Roast for 30 minutes or so, stirring occasionally, until just tender, then remove from the oven and set aside.
Meanwhile, put the coconut, turmeric, ginger, green chillies and 1 tsp salt in a blender, then add a little of the buttermilk. Blitz, then drain the cashews and melon seeds, add to the blender and blitz again to form a smooth paste – add a little more buttermilk if needed. Set aside.
Heat the oil in a large saucepan or casserole dish. Add the mustard and cumin seeds and the dried chilli(es), then cook until they start to sizzle and pop. Add the curry leaves and nut paste, then stir-fry over a medium high heat for a few minutes. Add the rest of the buttermilk, the beans, and the chard stalks. Cook for around 5 minutes, then add the chard leaves and the roasted pumpkin. Simmer for a few minutes until the vegetables are tender and the sauce thick and creamy. Serve sprinkled with fresh coriander and lime wedges to squeeze over.