Preheat the oven to 350°F Peel and de-seed the squash. Cut into 2-inch chunks and toss with 1 tbsp of the olive oil on a baking tray. Roast for 30 minutes until starting to brown around the edges. Set aside to cool.
Heat the remaining oil in a large, deep skillet over a medium heat. Add the onion and cook until translucent – about 5 minutes. Add the garlic and ginger and stir for 1 minute. Add in the tomatoes, spices, salt, tomato paste, red pepper flakes and 1 cup of water. Bring to a boil and turn down to simmer. Leave to cook until most of the water has evaporated.
Pour the contents of the skillet into a blender and add the remaining 1 cup of water. Blend until smooth then pour back into the pan.
Add the coconut milk, chickpeas and roasted squash. Simmer until slightly reduced and thickened. Serve hot with rice.