Pat the chicken thighs dry and season both sides with salt and pepper.
4 chicken thighs, 1 pinch salt, 1 pinch pepper
In a large oven-safe skillet, heat olive oil over medium-high. Sear thighs skin-side down until golden (about 5–6 minutes), then flip and brown the other side for 2 minutes. Remove thighs and set aside.
1 tbsp olive oil
Lower heat to medium. Add the sliced onion and garlic. Sauté until softened and lightly caramelized, about 4 minutes.
1 small onion, 1 clove garlic
Pour in apple cider and chicken broth, scraping any browned bits from the pan. Stir in thyme and add apple slices.
1 cup apple cider, ½ cup chicken broth, 1 tsp dried thyme, ½ small apple
Nestle the chicken thighs into the liquid, skin-side up. Transfer the skillet (uncovered) to a preheated oven at 375°F (190°C). Bake for about 30 minutes, until the internal temperature reaches 165°F (74°C) and the sauce is lightly reduced.
Remove from the oven, spoon some of the pan sauce over the chicken, and serve.