Peel and roughly chop the onion.
In a large saucepan, heat the olive oil then gently cook the onions over a low-medium heat until translucent.
Meanwhile, de-seed, peel and chop the pumpkin or squash into rough cubes. Peel the carrot and roughly chop.
Add the pumpkin and carrot to the pan and cook for 5 minutes.
Add the curry powder and cook for a further minute or so until fragrant.
Crumble in the two stock cubes and pour over boiling water until the vegetables are just covered in the pan.
Bring to the boil and cook for 15-20 minutes until the vegetables are cooked through.
Whizz with a stick blender until smooth.
When ready to serve, ladle the soup into bowls.
Spoon natural yogurt into a disposable piping bag or freezer bag.
Snip off the corner of the bag, then pipe a spiral of yogurt onto the top of each bowl of soup.
Working from the middle, drag a cocktail stick through the surface of the soup to create a spider web effect.
Serve immediately and enjoy!