Preheat oven to 425° F and arrange onion slices in bottom of a large, heavy-duty 12” skillet with high sides.
Remove and discard neck and giblets from chicken and place bird breast-side up on top of onion slices in skillet. Pat chicken dry with paper towels and generously season the outside with salt and black pepper.
Separate out approximately 1/3 of the fresh thyme, rosemary, and sage from the bundle. Remove and discard the tough stems from the thyme and rosemary leaves. Combine the leaves with the sage before roughly chopping.
Add the softened butter, half the minced garlic, and the chopped fresh poultry herbs in a small bowl and stir to combine. Divide the herb butter into small chunks before tucking evenly under the chicken skin covering the breast meat.
Massage the remaining minced garlic inside the cavity of the bird before stuffing with the remaining fresh poultry herbs. Secure legs together with kitchen string, and then add the chicken broth to the skillet.
Place skillet in pre-heated oven and roast for 1 hour and 30 minutes or until a meat thermometer inserted into the thickest part of the thigh reads 165° F. Check every 30 minutes while cooking to make sure the skin isn’t becoming too brown. If it is, cover with aluminum foil after 1 hour and check for doneness after another 15-20 minutes.
Remove skillet from oven and carefully transfer chicken to a serving platter.When lifting the chicken out of the skillet, use a wooden spoon inserted into the cavity and tilt the chicken so the juices run into the skillet. Cover loosely with aluminum foil to keep warm and let rest for 15-20 minutes.
While the chicken rests, discard the onion slices in the skillet and heat the remaining liquid over medium-high heat. Scrape the bottom of the skillet with a spatula or wooden spoon to remove the browned bits. Continue cooking until the liquid is reduced by one half. Once reduced, taste and season with salt and black pepper, if desired.
To serve, carve the chicken and top each serving with a spoonful of the warm pan sauce. Enjoy!