This soup is phenom and only takes a few minutes to pull together! Under 30, seriously, since it's vegetarian. It's earthy, rustic, fresh, comforting, simple, complex, bright, light, noodle-y and yumtastic.
Bring the stock and miso paste to a simmer in a medium pot or Dutch oven over medium-high heat, stirring to dissolve the paste. Add the noodles, corn and mushrooms. Stir in the soy sauce and juice from half the lime. Simmer until the noodles are al dente, about 4 minutes.
Ladle the soup between 2 big bowls and garnish with the scallions. Finish with more lime juice if desired.
You can sub in whatever type of miso paste you have.