01 - Pat chicken breasts dry with paper towels. Season both sides generously with salt, black pepper, and garlic powder, pressing the spices into the meat to adhere.
02 - Heat olive oil and butter in a large skillet over medium-high heat until shimmering. Add chicken breasts and sear for 5-6 minutes per side until golden brown and cooked through (internal temperature reaches 165°F). Transfer to a plate and tent with foil to rest.
03 - Add minced garlic to the same skillet and sauté for 30 seconds until fragrant, being careful not to burn. Stir in chopped sun-dried tomatoes and cook for 1 minute to release their oils.
04 - Pour in chicken broth, using a wooden spoon to scrape up any browned bits from the bottom of the pan. Reduce heat to medium-low.
05 - Add heavy cream, grated Parmesan cheese, and Italian seasoning. Stir constantly until cheese melts and sauce thickens slightly, about 2-3 minutes.
06 - Add fresh spinach leaves to the sauce, stirring gently until just wilted, about 1 minute. Do not overcook.
07 - Return chicken breasts to the skillet, spooning sauce generously over the top. Simmer for 3-4 minutes until chicken is heated through. Serve immediately, garnished with chopped fresh basil and additional Parmesan cheese if desired.