How to Make It
Preheat oven to 375°F.
Heat a Dutch oven over medium-high. Add barley to dry pan; cook 8 minutes or until deeply browned. Remove from pan.
Add oil to pan; swirl. Sprinkle chicken with 1/2 teaspoon salt and 1/2 teaspoon pepper. Add chicken to pan, breast side down; cook 6 minutes. Carefully turn chicken over; cook 4 minutes. Remove from pan.
Add light-green onion parts, ginger, and garlic to pan; cook 2 minutes, stirring frequently. Add remaining 1/4 teaspoon salt, remaining 1/4 teaspoon pepper, stock, miso, and vinegar. Bring to a boil, stirring to dissolve miso and loosen browned bits. Add barley and chicken to pan. Cover and bake at 375°F for 45 minutes.
Arrange bok choy halves around chicken; cover and bake at 375°F for 15 more minutes. Uncover, and sprinkle dark-green onion parts and cilantro over chicken mixture.