Boil the Dashi broth in a pot and stir in the Miso paste until dissolved.
Add in noodles and allow to cook.
Stir in tofu (if using), and chopped scallions. Allow to cook for another minute or so. Serve immediately.
Notes
Making Dashi broth from scratch:
Water, kombu (dried kelp), and bonito fish flakes.
Red Miso vs White Miso
White Miso is made with soy beans fermented with rice, whereas Red Miso is soy beans fermented with barley or other grains, and fermented with either higher percentage of soy beans or fermented for a longer period of time. In contrary to Red Miso's deep umami flavours, White Miso carries a lighter and sweeter flavour.