Boil the whole sweet potatoes until fork tender. Allow to cool slightly, peel and mash or blend until smooth.
Add the sweet potato puree, flour and salt to a large bowl and mix until a dough forms. Knead for 6-8 minutes until smooth, adding a little extra flour if needed.
For the sauce, heat the butter in a large frying pan until nutty and browned, then whisk in the miso until smooth. Set aside.
Bring a large pot of salted water to a gentle simmer. Using lightly oiled kitchen scissors, snip small pieces of dough directly into the water. Once all the dough has been cut, bring to a boil and cook for about 3 minutes, or until the noodles float to the surface.
Add the noodles straight into the sauce with the reserved hot cooking water and toss until a glossy emulsified sauce forms. Top with spring onions, sesame seeds and seaweed, then DEVOUR.
