In a small bowl, melt butter in the microwave. Add thyme leaves and freshly ground pepper to the melted butter and stir. Set aside to allow flavors to meld and butter to cool.
Rinse chicken breasts and pat dry with paper towels. Place chicken breasts, breast side up into roasting pan.
Brush melted butter all over the surface of the chicken. Sprinkle any thyme remaining in the butter dish onto the chicken.
Bake uncovered 45-55 minutes, or until juices run clear and chicken registers 165 ° F. Time will vary based on the size of your chicken breasts.
Remove from oven and allow to rest for 5-7 minutes before serving.
Notes
Be sure to melt the butter and mix it with your herbs first. This will allow time for the butter to soak up some of the lemon flavor from the fresh thyme while your are readying the chicken.If you use very large chicken breasts, use a roasting pan with a wire rack to allow the meat to sit above the bottom of the pan. Because it will require a bit longer to cook, your butter and any fat drippings from the chicken skin could begin to smoke, so add about a cup of water to the bottom of the pan before placing in the oven.