Peel and finely chop the onion. Warm a large pan on a medium heat for a 2 mins then pour in 1 tbsp olive oil. Add the onion to the pan and fry gently for 8 mins till it’s soft but not coloured.
While the onion is cooking, peel and grate the garlic and ginger. Trim and roughly chop the carrots (no need to peel). Fill and boil the kettle.
When the onion has cooked for 8 mins, add the ginger and garlic to the pan. Fry together for 2 mins, stirring, then add the carrots with a good pinch of salt and pepper. Pour in 700ml hot water from the kettle. Crumble in the coconut cream and stir well. Pop a lid on the pan and simmer for 20 mins till the carrots are tender.
Finely grate or pare the zest from the lime and cut the lime into 4 wedges.
Using a hand blender, blitz the soup till smooth and creamy. Squeeze in the juice from 2 of the lime wedges in to the soup and stir. Taste and add more salt, pepper or lime juice if you think it needs it. Ladle the soup into warm bowls and top with the mixed seeds and lime zest to serve.