Pat chicken dry and season well with salt and pepper. Heat olive oil in a large skillet over medium-high. Sear chicken skin-side down for 5–7 minutes until golden, flip, and cook 3–4 more minutes. Set aside.
In the same pan, sauté onion for 3–4 minutes until soft. Add bell pepper and cook another 3–4 minutes. Stir in garlic and cook 1 minute until fragrant.
Optional: Add wine to deglaze, scraping up browned bits. Simmer 2–3 minutes. Stir in cherry tomatoes, diced tomatoes, broth, olives, oregano, thyme, and red pepper flakes.
Return chicken to the pan, skin-side up, nestled into the sauce. Cover, reduce heat to low, and simmer 30–35 minutes until tender and cooked through (165°F).
Remove from heat. Top with fresh parsley and serve hot.