200g (7 oz) dried spaghetti
50g (1.7 oz) unsalted butter
400g (14 oz) mixed mushrooms, cut into rough chunks (e.g. shitake, oyster, shimeji, enoki)
3 garlic cloves, finely chopped
3 tbsp miso paste*
½ cup finely sliced spring onion
¼ cup grated parmesan, plus extra to serve
salt





