Pat the chicken breasts dry with paper towels. Pound them to an even thickness, about ¾ inch, so they cook evenly. Season both sides generously with salt, pepper, and dried Italian seasoning.
Heat 2 tablespoons of olive oil in a large skillet over medium-high heat. Once shimmering, add the chicken breasts. Cook undisturbed for 3-4 minutes until golden brown on one side, then flip and cook another 3 minutes. Remove chicken to a plate and tent with foil.
Reduce heat to medium. In the same skillet, add minced garlic. Stir constantly for about 30 seconds until fragrant but not browned. Add chopped sun-dried tomatoes and cook for 2 minutes, stirring occasionally.
Lower heat to medium-low. Add cream cheese to the skillet, stirring until melted and combined with garlic and tomatoes. Pour in heavy cream and stir constantly until sauce is smooth and starts to thicken, about 3-4 minutes. Stir in grated Parmesan cheese until melted. Season with salt and pepper to taste.
Add fresh spinach to the sauce and stir until wilted, about 1-2 minutes. Return chicken breasts to the skillet, nestling them into the sauce. Cover and simmer on low for 3-4 minutes, or until chicken reaches an internal temperature of 165°F.
Serve the chicken with creamy sauce spooned over the top. Pair with garlic mashed potatoes, buttered pasta, or your preferred side.
