Heat olive oil in a large skillet over medium-high heat. Cook chicken until browned and no longer pink in the center, 3 to 5 minutes per side. Remove chicken and set aside on a plate.
Add heavy cream, chicken broth, Parmesan cheese, garlic powder, and Italian seasoning to the skillet. Whisk sauce over medium-high heat until starting to thicken, about 5 minutes. Add spinach and sun-dried tomatoes; simmer until spinach starts to wilt, about 1 minute. Return chicken to the skillet and cook until heated through, 2 to 3 minutes.
