Create your flavor base: In a large pot over medium heat, add 2 tablespoons of water or oil. Add the sliced onions and sauté for 3-4 minutes until translucent. Add the minced garlic and grated ginger, cooking for another 30 seconds until fragrant.
Build the broth: Pour in the vegetable broth and bring to a gentle simmer. In a small bowl, whisk the miso paste with about ½ cup of the hot broth until smooth, then return this mixture to the pot. This prevents the miso from clumping.
Add remaining broth ingredients: Stir in the tahini or peanut butter, chili oil, soy sauce, rice vinegar, and maple syrup. Allow the flavors to meld for about 5 minutes on low heat, being careful not to boil the broth after adding miso (high heat destroys its probiotic benefits).
Cook the vegetables: Add the carrots and mushrooms to the simmering broth. Cook for about 5-7 minutes until the vegetables begin to soften but still maintain some bite.
Prepare the noodles: Add the ramen noodles directly to the pot and cook according to package instructions, usually 2-3 minutes for fresh noodles or 4-5 minutes for dried ones. Stir occasionally to prevent sticking.
Finish with greens: Just before serving, stir in the spinach or bok choy and allow to wilt for about 30 seconds.
Serve immediately: Ladle the ramen into bowls, ensuring each portion gets a good mix of noodles, vegetables, and broth. Top with sliced green onions and any optional toppings of your choice.