Season the chicken breasts with salt, pepper, and Italian seasoning on both sides.
In a large skillet, heat olive oil and butter over medium heat. Add the chicken breasts and cook for about 6-7 minutes on each side until golden brown and cooked through. Remove from the skillet and set aside.
In the same skillet, add the minced garlic and sauté for about 30 seconds until fragrant. Add the cherry tomatoes and cook for 2-3 minutes until softened.
Stir in the fresh spinach and cook until wilted. Pour in the heavy cream and bring it to a simmer.
Add the grated Parmesan cheese to the sauce, stirring continuously until it melts and becomes creamy. Season with salt and pepper to taste.
Return the seared chicken breasts to the skillet, spoon the sauce over them to coat evenly, and let it simmer for another 2-3 minutes.
Once everything is heated through, remove from heat. Garnish with fresh basil leaves before serving.
Notes
Serve with pasta or crusty bread to soak up the sauce.