The noodles are not rinsed and they are not boiled separately first. They go into the pot raw, with the dusting flour still on them, straight in among the vegetables.

That flour dissolves into the broth and thickens it. A thickened broth holds its heat, which is the reason this gets made in the cold months and not in the summer. The noodles swell as they drink, and their edges go soft against each other in the pot.

The seasoning depends on where in the prefecture you are. In the north and the west it is usually miso; in the east it is usually soy sauce; in the middle you will find both, sometimes in the same village. Hoto, over the mountains in Yamanashi, is miso and stays miso; here soy sauce has spread across a good part of the prefecture. One name, and the recipe splits along lines nobody drew on purpose.

The dough takes less than two-thirds of the water that goes into hoto or into ordinary udon, which is why it holds up to being cooked in the soup. This is wheat country, double-cropped, and flour has been an everyday food here rather than a substitute for rice. It was not what you ate when the rice ran out. It was simply what you ate.