Preheat your oven to 400°F (200°C).
In a large bowl, combine the sliced mushrooms, chopped onion, minced garlic, thyme, rosemary, salt, and pepper. Drizzle with 2 tablespoons of olive oil and toss to coat.
In a large oven-safe skillet, heat the remaining olive oil over medium-high heat. Add the chicken thighs, skin side down, and sear for about 5 minutes until golden brown. Flip the chicken and sear the other side for an additional 5 minutes.
Remove the chicken from the skillet and set aside. In the same skillet, add the mushroom mixture and sauté for about 3-4 minutes until the onions are translucent.
Pour in the chicken broth and stir to combine. Nestle the chicken thighs back into the skillet, skin side up.
Transfer the skillet to the preheated oven and bake for 30-35 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C).
Remove from the oven and let it rest for 5 minutes. Garnish with fresh parsley before serving.