01 - Pat chicken thighs dry with paper towels. Season both sides with salt and black pepper.
02 - Heat olive oil in a large skillet over medium-high heat. Add chicken thighs and sear for 3–4 minutes per side, until golden brown. Remove chicken and set aside.
03 - In the same skillet, add garlic and sauté for 30 seconds until fragrant.
04 - Pour in apple cider, apple cider vinegar, Dijon mustard, honey, brown sugar, thyme, and cinnamon. Stir and bring to a simmer.
05 - Return the chicken to the skillet. Reduce heat to medium-low. Cover and cook for 15 minutes, turning chicken halfway.
06 - Uncover and increase heat to medium-high. Cook for an additional 7–10 minutes, spooning sauce over chicken, until sauce is reduced and sticky.
07 - Stir in the butter until melted and glossy.
08 - Remove from heat. Garnish with chopped parsley before serving.