Place butter in medium microwavable bowl. Microwave uncovered on High 30 to 45 seconds or until melted. Add Buffalo wing sauce and celery seed; stir to combine. Reserve 2 tablespoons sauce mixture in small bowl; set aside. Add chicken breasts to remaining sauce mixture; toss to coat. Transfer chicken to cookie sheet; bake 15 to 20 minutes or until juice of chicken is clear when center of thickest part is cut (at least 165°F).