Prepare the chicken: If the chicken breasts are thick, slice them in half or pound them to an even thickness.
Season the chicken: Sprinkle both sides with salt and black pepper for added flavor.
Sear the chicken: Heat olive oil in a skillet over medium heat. Add the chicken and cook for about 5 minutes per side until golden brown. Remove from the skillet and set aside.
Make the sauce: In the same skillet, melt the butter and add minced garlic. Sauté for about 30 seconds until fragrant.
Add the liquid ingredients: Pour in the chicken broth and lemon juice, scraping up any browned bits from the pan. Let it simmer for 2 minutes.
Stir in the cream and Parmesan: Slowly add the heavy cream and Parmesan cheese, stirring continuously until the sauce thickens slightly.
Add the spinach: Stir in the fresh spinach and cook for about a minute until it just starts to wilt.
Return the chicken: Place the cooked chicken back into the skillet, letting it simmer in the sauce for another 3-4 minutes.
Serve and enjoy: Plate the chicken with extra sauce spooned over the top, garnishing with additional Parmesan if desired.