Preheat your oven to 375°F (190°C).
In a small bowl, mix together garlic powder, onion powder, smoked paprika, salt, and black pepper.
Rub the spice mixture all over the chicken breasts to ensure an even coating.
In a large oven-safe skillet, heat the olive oil over medium-high heat. Once hot, add the chicken breasts and sear for 5-7 minutes on each side, until golden brown.
Remove the chicken from the skillet and set aside. In the same skillet, add the chicken broth and scrape any browned bits from the bottom.
Stir in the heavy cream and bring to a gentle simmer. If using, add the chopped spinach and let it wilt for a minute.
Return the chicken breasts to the skillet and sprinkle with Parmesan cheese.
Transfer the skillet to the preheated oven and bake for an additional 15-20 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (74°C).
Remove from the oven, garnish with chopped parsley, and serve warm.