Teriyaki Chicken Noodle Soup

Name: Teriyaki Chicken Noodle Soup
Ingredients: 1 tablespoon toasted sesame oil; 4 scallions, chopped (white and green parts separated); 1 2-inch piece ginger, peeled and finely chopped; 2 cloves garlic, minced; 2 cups low-sodium chicken broth; 2 large skinless, boneless chicken breasts (about 8 ounces each); 2 tablespoons teriyaki sauce; Kosher salt; 1 cup chopped delicata or other winter squash; 9 ounces fresh Asian egg noodles; 1 red, yellow or orange bell pepper, thinly sliced; 1 5-ounce package baby spinach (about 8 cups)