Place the stock, chilli, sugar and soy in a large saucepan over high heat and bring to the boil. Add the mushrooms, reduce the heat to low and simmer for 10 minutes. Add the noodles and cook for a further 2−3 minutes or until the noodles are tender. Ladle the soup into bowls and top with the green onions. Serve with the sesame seeds. Serves 4.
* Somen noodles are thin white Japanese noodles made from wheat flour. Usually sold dried, they’re available from Asian grocery stores.