Step 1: Preheat Oven and Prepare Vegetables: Preheat oven to 400F (200C). While the oven heats, prepare the vegetables by quartering the potatoes, wedging the onion, chopping the carrots and celery, and mincing the garlic. This ensures the vegetables cook evenly and develop optimal flavor.
Step 2: Season Chicken: Pat the chicken thighs dry with paper towels. This helps the skin crisp up during baking. In a small bowl, combine olive oil, thyme, rosemary, salt, and pepper. Rub the mixture all over the chicken thighs, ensuring they are evenly coated with the herbs and spices. The olive oil helps the spices adhere to the chicken and promotes browning.
Step 3: Arrange Vegetables: In a large bowl, toss the potatoes, onion, carrots, and celery with the remaining olive oil mixture, ensuring they are evenly coated. Spread the vegetables in a single layer on a large baking sheet or roasting pan. This promotes even cooking and prevents steaming.
Step 4: Add Chicken to Pan: Nestle the seasoned chicken thighs among the vegetables on the baking sheet, skin-side up. Ensure the chicken is not overcrowded, as this can prevent proper browning. The skin-side-up position ensures maximum crispiness.
Step 5: Bake the Chicken: Place the baking sheet in the preheated oven and bake for 40-45 minutes, or until the chicken is cooked through and the internal temperature reaches 165F (74C). The vegetables should be tender and slightly browned. If the vegetables start to brown too quickly, cover the pan loosely with foil.
Step 6: Add Broth (Optional): For a richer sauce, pour chicken broth over the vegetables during the last 15 minutes of cooking. The broth will deglaze the pan and create a flavorful pan sauce.
Step 7: Rest and Serve: Remove the baking sheet from the oven and let the chicken and vegetables rest for 5-10 minutes before serving. This allows the juices to redistribute, resulting in more tender and flavorful chicken. Garnish with fresh parsley before serving.
Optional Tips: For extra crispy chicken skin, broil for the last 2-3 minutes, watching carefully to prevent burning. Substitute other root vegetables like parsnips or turnips for a different flavor profile. Add a squeeze of lemon juice to the vegetables before baking for a brighter flavor.