Heat the oil in a large saucepan on medium-high heat. Cook onion and celery, stirring, for 5 minutes, or until soft. Add the ginger, garlic and chilli and cook, stirring, for about 1 minute.

Add the sweet potato, pumpkin, chickpeas, stock and 2 cups of water, and bring to the boil. Reduce heat and simmer, uncovered, for 20 minutes, or until vegetables are very tender. Set aside to cool slightly.

Blend soup in batches until smooth. Return to clean saucepan and heat over medium heat until hot. Season with cracked black pepper. Sprinkle with pepitas and coconut, and serve with a wedge of lime.