1.Preheat oven to 200°C. Line an oven tray with baking paper.
2.Whisk 1 tablespoon miso, 2 tablespoons tamari and oil in a large bowl. Add pumpkin; toss to coat. Place pumpkin, in a single layer, on tray. Roast for 40 minutes or until golden and tender.
3.Meanwhile, bring the water, ginger and remaining miso to the boil in a large saucepan. Add noodles and gai lan; return to the boil. Reduce heat; simmer, for 2 minutes or until noodles are tender. Stir in remaining tamari; season to taste.
4.Divide pumpkin and broth into bowls; sprinkle with seaweed, green onion and seeds. Serve with warm flatbread, if you like.
Just before serving, you could sprinkle this dish with a little shichimi tōgarashi – a Japanese spice powder (literally meaning “seven flavour chilli pepper”). In addition to the chillies, other ingredients can include: sichuan pepper, dried citrus peel, sesame seeds, poppy seeds, hemp seeds, ginger, garlic, shiso, and nori. It is readily available from Asian supermarkets. If unavailable you can use dried chilli flakes.