In a 4-to-5-quart pot, combine boneless skinless chicken thighs, thinly sliced garlic, finely chopped ginger, scallion whites, kosher salt, freshly ground pepper, and 10 cups of water. Bring this mixture to a vigorous boil over high heat.

Once boiling, reduce the heat to medium-low and let the soup simmer uncovered for approximately 15 minutes.

While the soup simmers, whisk together black rice vinegar, soy sauce, and toasted sesame oil in a separate bowl. Add crispy chili oil to taste.

After the chicken has simmered, carefully remove it and add dried ramen noodles and carrot matchsticks to the boiling broth.

Use two forks to shred the cooked chicken into bite-sized pieces. Return the shredded chicken to the pot with the noodles and broth.

Gently rewarm the soup over low heat for about one minute. Adjust seasoning if necessary.

Ladle the soup into bowls and top each serving with reserved green parts of the scallions and drizzle with sauce before serving.