Preheat your oven to 375°F (190°C).

In a small saucepan, combine the apple cider, apple cider vinegar, brown sugar, Dijon mustard, dried thyme, garlic powder, salt, and pepper. Bring the mixture to a simmer over medium heat, stirring occasionally until the sugar dissolves and the glaze thickens slightly, about 10 minutes.

While the glaze is simmering, heat olive oil in a large, oven-safe skillet over medium-high heat. Season the chicken thighs with salt and pepper.

Once the oil is hot, place the chicken thighs skin-side down in the skillet. Sear for about 5-7 minutes until the skin is golden brown and crispy. Flip the chicken and sear the other side for another 3-4 minutes.

Pour the cider glaze over the seared chicken, making sure to coat each piece evenly.

Transfer the skillet to the preheated oven and bake for 25-30 minutes, or until the chicken reaches an internal temperature of 165°F (74°C).

Remove the skillet from the oven, and let the chicken rest for about 5 minutes. The glaze will continue to thicken as it cools.

Garnish with fresh thyme sprigs before serving.