Season chicken breasts with salt, pepper, and Italian seasoning on both sides.
Heat olive oil in a large skillet over medium-high heat and cook chicken for 5-6 minutes per side until golden and cooked through, then remove and set aside.
In the same skillet, add garlic and cook for 30 seconds until fragrant.
Add heavy cream, chicken broth, and sun-dried tomatoes, stirring to combine and scraping up any browned bits from the bottom.
Bring to a simmer and cook for 3-4 minutes until slightly thickened.
Stir in spinach and parmesan cheese, cooking until spinach wilts and cheese melts.
Return chicken to the skillet, spoon sauce over the top, and cook for 2 minutes to reheat before serving.