Prep your add-ins: Slice mushrooms, chop greens, and thinly slice scallions.
Shred or chop the cooked chicken. Have everything ready so the soup moves fast.
Build the aromatic base: Heat the neutral oil in a medium pot over medium heat. Add garlic and ginger.
Cook 30–45 seconds, stirring, until fragrant but not browned.
Sauté the mushrooms: Add mushrooms and a pinch of salt. Cook 2–3 minutes until softened and lightly browned around the edges.
Add the broth and seasonings: Pour in chicken broth. Stir in soy sauce and sesame oil.
Bring to a lively simmer over medium-high heat.
Stir in miso (if using): Ladle a bit of hot broth into a small bowl, whisk in the miso until smooth, then return it to the pot. This keeps it silky and prevents clumps.
Add the chicken: Stir in the shredded chicken and simmer 1–2 minutes to warm through. Taste and adjust with more soy sauce or a pinch of salt if needed.
Cook the noodles: Drop in the ramen bricks and cook according to package time, usually 2–3 minutes.
Stir gently to separate the strands.
Add the greens: In the last 30–60 seconds, toss in spinach or bok choy. They should wilt but stay bright.
Finish with acidity and heat: Turn off the heat. Stir in rice vinegar and add red pepper flakes or a drizzle of chili oil to taste.
Serve and top: Ladle into bowls.
Finish with scallions and any toppings you like—soft-boiled egg, sesame seeds, nori, or a squeeze of lime.