Season the chicken breasts with salt, pepper, and Italian seasoning. In a large skillet, heat the olive oil over medium heat. Add the chicken breasts and cook for about 6-7 minutes on each side or until cooked through and golden brown. Remove the chicken from the skillet and set aside.
In the same skillet, add the minced garlic and sauté for about 1 minute until fragrant. Then add the chopped spinach and cook until wilted, about 2-3 minutes.
Lower the heat and pour in the heavy cream while stirring continuously to combine with the spinach and garlic. Gradually add the grated Parmesan cheese, stirring until the cheese has melted and the sauce is creamy. Season with additional salt and pepper if needed.
Return the chicken breasts to the skillet, spooning the creamy spinach sauce over them. Let them simmer together for about 2-3 minutes, allowing the flavors to meld.
Transfer the Chicken Florentine to serving plates and garnish with halved cherry tomatoes and fresh basil leaves for a burst of color and flavor.