01 -
Preheat oven to 175°C. Grease a 23x33 cm baking dish with cooking spray and set aside.
02 -
Pat chicken breasts dry with paper towels, then season evenly with kosher salt and black pepper.
03 -
In a heavy deep skillet over medium-high heat, heat 2 tablespoons of olive oil. Sear chicken for 5 minutes per side until browned. Transfer to prepared baking dish.
04 -
Add butter to the skillet and melt. Add quartered mushrooms and cook for 2 minutes until just golden. Transfer mushrooms to baking dish over the chicken.
05 -
Layer red bell pepper strips over mushrooms and chicken in the baking dish.
06 -
Return skillet to heat, add remaining olive oil, and sauté diced onion for 5 minutes until tender.
07 -
While onions cook, whisk together chicken broth, ketchup, tomato paste, honey, white wine vinegar, Worcestershire sauce, smoked paprika, and chili powder in a medium bowl.
08 -
Sprinkle flour over onions and cook for 1 minute. Gradually stir in whisked sauce mixture. Simmer 3–4 minutes, stirring, until slightly thickened.
09 -
Pour the hot sauce over chicken and vegetables in the baking dish. Cover tightly with aluminum foil.
10 -
Bake for 35 to 45 minutes, basting chicken with sauce at halfway point, until the chicken is cooked through.
11 -
Remove foil, baste again, and continue baking uncovered for 15 minutes until bell peppers caramelize and sauce thickens.