Season the chicken with 1 teaspoon of the kosher salt and ½ teaspoon black pepper, covering all sides.
Whisk together 1 teaspoon of the parsley, ¾ teaspoon thyme, ¾ teaspoon sage and 1 teaspoon of the rosemary. Sprinkle over all sides of the chicken. Cover and refrigerate 2 to 4 hours or overnight.
When you’re ready to roast, remove the chicken from the refrigerator and let it rest at room temperature for about 30 minutes. Preheat the oven to 425-degrees.
Toss the carrots, onions and shallots with 3 tablespoons of the olive oil, the remaining ½ teaspoon kosher salt, ¼ teaspoon pepper, ½ teaspoon of parsley, ¼ teaspoon thyme, ¼ teaspoon sage and ½ teaspoon rosemary.
Place the slices of lemon in the bottom of a roasting pan that has been lightly sprayed with a cooking spray. Place the chicken on top of the lemon and spread the vegetables in and around the chicken. Nestle the bay leaves into the vegetables and drizzle the remaining olive oil over the top of the chicken.
Roast in a 425-degree oven until the internal temperature of the chicken reaches 165-degrees and the juices run clear, about 45 to 50 minutes.
Transfer the chicken and vegetables to a platter using a slotted spoon and cover with foil to rest while you make the sauce.
Place the roasting pan over medium heat and add the balsamic vinegar to the pan drippings. Continue cooking until the vinegar and drippings are reduced slightly, about 5 minutes.
Add the butter, whisking it into the drippings and vinegar. Once the butter has melted, whisk in the flour, about 2 tablespoons at a time. Cook for 2 minutes, whisking frequently.
Pour in the chicken stock and whisk until smooth. Reduce the heat to medium-low heat and continue cooking until the sauce has thickened, about 5 to 7 minutes.
Many bone-in chicken breasts are quite large and perfect for hearty appetites but feel free to carve portions for more servings.