01 - Season chicken breasts generously with salt, black pepper, and Italian seasoning on both sides, ensuring even coverage.
02 - Heat olive oil and butter in a large skillet over medium-high heat. Add chicken breasts and cook for 5-7 minutes per side until golden brown and internal temperature reaches 165°F. Remove chicken and set aside on a plate.
03 - Reduce heat to medium. Add onion and garlic to the same skillet; sauté for 2-3 minutes until fragrant, translucent, and lightly golden.
04 - Pour in chicken broth, scraping up browned bits from the bottom of the skillet with a wooden spoon. Let simmer for 2 minutes to reduce slightly.
05 - Stir in heavy cream and Parmesan cheese, whisking continuously until sauce is smooth and cheese has melted. Simmer gently for 2-3 minutes until slightly thickened and coating the back of a spoon.
06 - Return chicken to the skillet, spooning sauce over the top. Simmer for 3-5 minutes until chicken is heated through and flavors have melded.
07 - Sprinkle with fresh chopped parsley and additional Parmesan cheese if desired. Serve immediately accompanied by mashed potatoes, pasta, or steamed vegetables.