Start by making a simple broth for the ramen: Place the dried shiitake mushrooms in a jug or bowl (large enough to hold 500 ml), add the kombu if using and, if not, add a vegetable stock cube and 1 tablespoon of soy sauce. Cover with 500 ml of boiling water and set aside to soak and soften.
Cut up the tofu into small chunks, and add to a mixing bowl. Sprinkle over the cornflour, and season well with salt and pepper. Toss the chunks of tofu in the bowl so that the pieces are well covered.
Add vegetable oil to a frying pan and, once warm, fry the pieces of tofu evenly on all sides until crispy and golden. This should take 5-10 minutes.
While the tofu cooks, thinly slice the garlic and ginger and get a small saucepan ready.
Now bring it all together: To the small saucepan, add 1 tablespoon of sesame oil and add the ginger and garlic. Lightly fry these for a few minutes and then strain in the shitake and seaweed stock through a sieve. Reserve the shitake mushrooms and thinly slice. Bring the pan to a gentle simmer, and add the oat milk and miso paste. Stir well and keep on a rolling boil for 5 minutes to concentrate the flavours. Check for seasoning, add a dash of soy sauce if it needs more saltiness.
Meanwhile, cook the noodles according to the packet instructions and then drain into the serving bowl. Strain the hot ramen broth over the noodles.
Top with the slices of shitake mushrooms and crispy tofu. Add crispy chilli oil, sesame seeds and spring onions to finish.