Peel the butternut squash using a potato peeler, then cut in half, de-seed and cut into small chunks. Drizzle over a little rapeseed oil, then roast for around 30 minutes until soft.
While the butternut squash is roasting, heat the rapeseed oil over a medium heat then gently fry the onions until they are translucent. Add the garlic and ginger and cook for a further minute or two until it is fragrant but not browning.
Add all of the spices, chopped tomatoes, tomato puree, coconut milk, tahini, water and milk then stir well and bring to a simmer.
Pour into a blender along with the roasted butternut squash and mango then blend until smooth and creamy.
Serve with a drizzle of greek yogurt and chopped coriander.