Layer the chicken breasts in the bottom of the crockpot.
Pour the salad dressing over the chicken breasts completely coating.
Cook for 4-6 hours on high, 8-10 hours on low.
For Oven:
Heat oven to 375 degrees F. Spray 13x9-inch pan with cooking spray.
Layer chicken breasts in a glass baking dish.
Pour the salad dressing over the chicken breasts, completely coating.
Cover with foil; bake 20 minutes. Turn chicken; bake uncovered 20 to 30 minutes longer or until juice of chicken is clear when center of thickest part is cut.
For Stovetop:
Spray a large heavy skillet with cooking spray, place on medium high heat and brown chicken. When browned on both sides, pour in the Salad Dressing and simmer, turning chicken once, until cooked through, about 15-20 minutes longer.