Pat the chicken pieces dry with a paper towel and lay them, skin side up, on a baking sheet. Place the cookie sheet, uncovered, in the refrigerator for at least 8 hours. Take the chicken out 45 minutes before baking to bring them to room temperature.
Preheat the oven to 500 degrees F.
Separate the layers of the onion and distribute them across the baking sheet. Add the garlic cloves, lemon slices, and finally the herb sprigs. Nestle the chicken pieces on top and season generously with salt and pepper.
Roast for 45 minutes or until the juices are running clear.
I don't mind serving straight from the baking sheet, but it's beautiful to spoon the onions, garlic, lemons, and herbs onto a gorgeous platter and put the chicken pieces on top.