Peel & chop the onion.
Wash the fennel bulbs and courgettes, then dice quite finely, keeping the feathery green bits at the top of the fennel to garnish when serving.
Spray the oil into a heavy based saucepan or casserole over a medium heat. Fry the onion until softened. Stir in the curry powder.
Add the fennel and courgette and cook for a couple minutes, stirring. Add the stock, bring to a simmer then cover and cook for 10-12 minutes over a low heat.
Use a hand blender to smooth the soup and season to taste freshly ground salt and pepper.