Pat chicken dry; season with salt, pepper, and Italian seasoning.
Heat olive oil in a large skillet over medium-high. Sear chicken 5–6 minutes per side until golden and cooked through (165°F). Remove to a plate.
In the same skillet, sauté garlic 30 seconds until fragrant. Pour in chicken broth, scraping up the browned bits.
Stir in heavy cream and Parmesan; simmer 2–3 minutes until slightly thickened.
Stir in spinach until wilted. Return chicken to the skillet and spoon sauce over top. Garnish with parsley and serve over pasta or rice!