Pat chicken pieces dry with paper towels and season generously with salt and black pepper on all sides. This step ensures beautiful golden browning rather than steaming in the pan.
Heat olive oil in a large skillet over medium-high heat until it shimmers and moves freely. Wait approximately 2 minutes until the oil is genuinely hot before adding chicken to achieve proper searing.
Add chicken pieces to the hot skillet in a single layer without crowding the pan. Sear for 6-7 minutes without moving them, then flip and cook another 4-5 minutes until golden brown on both sides.
Transfer the seared chicken to a clean plate and set aside temporarily. Add diced onion and minced garlic to the same skillet, stirring constantly for 2-3 minutes until fragrant and softened.
Stir in sliced bell peppers and mushrooms, cooking for 3 minutes while stirring occasionally. This sizzling chicken skillet comes alive as the vegetables release their moisture and develop slight caramelization.
Return the chicken to the skillet along with chicken broth, paprika, oregano, and thyme. Simmer for 5-7 minutes until the chicken reaches 165°F internally and vegetables become tender.
Stir in butter and fresh lemon juice, tasting and adjusting seasonings as needed. Top with chopped fresh parsley just before serving for color and brightness.