1. Melt butter in a Dutch oven over medium-high heat. Sprinkle chicken thighs evenly with 1/2 teaspoon salt and 1/4 teaspoon pepper. Add chicken thighs to pan; sauté 3 minutes on each side or until browned. Remove chicken thighs. Add onion, carrot, and miso to pan; sauté 2 minutes, stirring occasionally. Add wine; cook 1 minute, scraping pan to loosen browned bits. Chop chicken thighs into bite-sized pieces; return chicken thighs to pan. Tie twine around herbs to secure. Add herbs, stock, celery, and chicken breast to pan; bring to a boil. Reduce heat, and cook for 5 minutes. Add remaining 1/4 teaspoon salt, 1/4 teaspoon pepper, and pasta; simmer for 2 minutes or until pasta is done. Discard herbs. Sprinkle with green onions.