Preheat the oven to 400°F (200°C).
Use the cut sides of the garlic halves to rub both sides of each chicken thigh, then set the garlic halves aside for later; season both sides of the chicken with salt and freshly ground black pepper.
Heat 1 Tbsp vegetable oil in a 12-inch oven-safe skillet over medium-high heat until hot.
Place the chicken thighs in the hot skillet, skin-side down if applicable, and cook until the bottoms are golden brown, about 8 minutes; drain off rendered fat from the pan once about halfway through cooking.
Transfer the seared chicken to a plate. Pour off most of the oil from the skillet, leaving about 1 teaspoon to coat the pan.
Thinly slice half of one lemon and arrange the reserved garlic halves and the lemon slices in the skillet.
Return the chicken to the skillet on top of the lemon and garlic, then sprinkle 1 Tbsp chopped fresh poultry herbs over the chicken.
Bake in the preheated oven until the chicken reaches 170°F (77°C) in the center on an instant-read thermometer, about 18 to 20 minutes.
Slice the roasted garlic halves into pieces and serve with the chicken; garnish with additional fresh herbs and serve lemon wedges for squeezing over the chicken.