01 - Preheat oven to 400°F. Lightly grease a medium baking dish with olive oil or cooking spray.
02 - Heat 1 tbsp olive oil in a large skillet over medium-high heat. Season chicken pieces with salt, pepper, and smoked paprika. Sauté for 4–5 minutes until lightly golden on all sides but not fully cooked through. Transfer to a plate and set aside.
03 - Add remaining olive oil to the same skillet. Sauté sliced onion for 2 minutes until translucent, then add minced garlic and cook for 30 seconds until fragrant.
04 - Add zucchini slices and chopped sun-dried tomatoes to the skillet. Cook for 3–4 minutes, stirring occasionally, until zucchini begins to soften but still retains some crunch.
05 - Stir in baby spinach and cook for 1–2 minutes until just wilted. Remove skillet from heat.
06 - In a mixing bowl, combine heavy cream, dried oregano, dried basil, chili flakes (if using), half the crumbled feta, and half the grated mozzarella. Season generously with salt and pepper, whisking until well incorporated.
07 - Transfer sautéed vegetables and seared chicken to the prepared baking dish, spreading evenly. Pour the cream mixture over the top, ensuring it coats all ingredients.
08 - Sprinkle the remaining feta, mozzarella, and all the Parmesan cheese evenly over the surface.
09 - Bake for 25–30 minutes until chicken is cooked through (internal temperature reaches 165°F), the sauce is bubbling, and the cheese topping is golden brown.
10 - Let the dish rest for 5 minutes to allow the sauce to set slightly. Garnish with fresh basil leaves and serve hot.