Step 1: Heat the Oven - Preheat your oven to 400°F. I like to get the oven fully hot before I start mixing anything because the rest of the prep moves quickly. Once the chicken is ready to bake, reduce the oven temperature to 350°F. This follows the original cooking method while giving the oven plenty of time to heat evenly before the casserole dish goes in.
Step 2: Mix the Honey Balsamic Marinade - Grab a large mixing bowl and add the balsamic vinegar, honey, minced garlic, dried thyme, dried oregano, chili pepper, salt, and black pepper. Cut the lemon and squeeze a little fresh juice into the bowl. Stir everything well until the honey has loosened into the vinegar and the herbs and garlic are spread throughout the mixture. You want the marinade to look dark, glossy, and evenly mixed so every piece of chicken gets the same balance of sweet, tangy, and savory flavor.
Step 3: Coat the Chicken Thoroughly - Add the boneless chicken thighs directly to the bowl with the marinade. Toss them well, turning each thigh several times so the balsamic mixture reaches every surface and gets into all those little folds. If you have extra time, cover the bowl and refrigerate the chicken for up to two hours. I usually make it right away on weeknights, but that short marinating time does give the herbs and garlic a chance to settle more deeply into the meat.
Step 4: Arrange the Chicken and Lemon - Reduce the oven temperature to 350°F, then transfer the chicken thighs to a casserole dish in a single layer. Pour the marinade from the bowl over the chicken so none of that good sauce gets left behind. Cut the rest of the lemon into wedges and tuck them around and over the chicken. Give the thighs a little room instead of packing them tightly together. That extra space helps the exposed edges roast rather than simply steam.
Step 5: Bake Until Tender - Place the casserole dish in the oven and bake for about 30 to 35 minutes. The exact cooking time can vary depending on the thickness of your chicken thighs, so use an instant read thermometer if you have one. The chicken is safely cooked when the thickest part reaches 165°F. By this point, the kitchen should smell sweet and garlicky, and the sauce around the chicken will have darkened and thickened slightly.
Step 6: Baste With the Pan Juices - About five minutes before the chicken is finished, carefully pull the dish partway out of the oven and spoon some of those hot balsamic pan juices over each thigh. This is a small step, but it makes a real difference. The extra coating keeps the surface moist and gives the honey another chance to become glossy and lightly caramelized as the chicken finishes baking.
Step 7: Rest, Garnish, and Serve - Take the chicken out of the oven once it has reached 165°F and let it sit for a few minutes before serving. Spoon a little more of the warm sauce from the bottom of the dish over each piece. If you have fresh thyme or basil around, scatter some over the top. Then bring the whole dish to the table while it is still warm and fragrant, with those roasted lemon wedges tucked between the chicken.