01 - Pat the chicken thighs dry. Season both sides with salt and pepper.
02 - Heat olive oil in a large skillet over medium-high heat. Add chicken thighs, skin-side down, and sear for 5–6 minutes until golden. Flip and cook for another 3–4 minutes. Transfer to a plate.
03 - In the same skillet, reduce heat to medium. Add butter, mushrooms, and onion. Sauté for 5–6 minutes until mushrooms are golden and onion is softened.
04 - Stir in garlic and cook for 1 minute until fragrant.
05 - Pour in chicken broth, scraping up any browned bits. Simmer for 2 minutes.
06 - Add heavy cream, Dijon mustard, thyme, oregano, and red pepper flakes. Stir to combine and bring to a gentle simmer.
07 - Return chicken thighs to the skillet, skin-side up. Spoon some sauce over. Cover and simmer for 15–20 minutes, until chicken is cooked through.
08 - Uncover and simmer for another 2–3 minutes to slightly thicken the sauce.
09 - Sprinkle with parsley and chives before serving.