Put 500g of the 600g of de-frosted sweetcorn into a food processor along with the coarsely chopped spring onions, garlic and red chilli. Blitz the mixture into a coarse paste.
Add the paste to a large saucepan with the corn flour and remaining sweetcorn.
Pour over the vegetable stock, bring the soup to a boil and simmer for 5 – 10 minutes.
Season to taste and then serve in bowls garnished with the remaining finely chopped spring onion.