Cut the courgettes into small pieces. Peel the potato and cut into small pieces.
Heat the oil in a large, heavy-based saucepan, add the onion and potato, stir everything around in the pan, then cover with a lid and leave to ‘sweat’ over a low heat for about 10 minutes.
Add the courgettes, cover and sweat for 5 minutes. Add about 100ml of the stock or water and cook for another 5 minutes until the potatoes are soft and the courgettes just cooked.
Take a couple of ladlefuls of the vegetables out of the pan and put into a bowl and, using a handheld blender, whizz until smooth (or blend in a food processor). This is a great purée for babies. Serve on its own or mix with baby rice.
Add the rest of the stock or water to the pan and cook for another couple of minutes and then purée until smooth.
Pour back into the pan and heat through. You can then add the cream cheese and mix together until the cheese has melted or serve the soup in bowls and top each with a little cream cheese. It is also lovely without the cheese if you don’t have any in your fridge.
Tip: this soup also works well with broccoli instead of courgettes.