Heat the vegetable oil in a pot, then add the star anise, cinnamon sticks, cloves and coriander seeds, then cook until fragrant (1 min)
Roughly chop the carrot, celery and onion, turn up the heat then add to pot, followed by garlic cloves and ginger
Turn up the heat, then cook for 10 minutes until the veg begins to char. Add the kombu, dried mushrooms, miso paste, veg stock if using, then water. Add a large pinch of salt and sugar, then soy sauce
Bring to a boil, then lower the heat and simmer until the broth turns golden-brown (45 minutes to 1 hour). Strain over a sieve into a saucepan, then season to taste and keep on a low heat
For the toppings, chop the tofu into strips, then fry until browned and season with soy sauce
Set aside the tofu, then fry the mushrooms in oil with some soy sauce and garlic until golden
Add the pak choi to the pan with a splash of water, cover and steam until cooked
Cook your noodles according to packet instructions, then chop the spring onion and herbs
To serve, add noodles into bowls, ladle broth to cover, then top with tofu, mushrooms, pak choi, herbs, spring onion, chilli and sesame seeds
