Preheat your oven to 400°F (200°C).
Season the chicken thighs with salt and pepper on both sides.
In a large oven-safe skillet, heat the olive oil over medium-high heat. Add the chicken thighs, skin-side down, and sear for about 5-7 minutes until the skin is golden brown. Flip the chicken and cook for another 3-4 minutes. Remove the chicken from the skillet and set aside.
In the same skillet, add the chopped onion and sauté for about 3-4 minutes until softened. Add the minced garlic and cook for an additional 1 minute until fragrant.
Pour in the white wine, scraping up any browned bits from the bottom of the skillet. Let it simmer for about 2-3 minutes to reduce slightly.
Stir in the chicken broth, heavy cream, thyme, rosemary, Dijon mustard, and lemon juice. Bring the mixture to a gentle simmer.
Return the chicken thighs to the skillet, skin-side up, and spoon some of the sauce over the top.
Transfer the skillet to the preheated oven and roast for 25-30 minutes, or until the chicken reaches an internal temperature of 165°F (75°C).
Remove from the oven and let it rest for 5 minutes before serving. Garnish with fresh parsley.