Season the boneless, skinless chicken breasts with salt and pepper on both sides. Heat a large skillet over medium-high heat and add a drizzle of olive oil. Once shimmering, place the chicken in the pan. Sear each side for about 4-5 minutes until golden brown and cooked through.

Remove the chicken from the skillet and set it aside. In the same skillet, add minced garlic and sauté for about 30 seconds until fragrant, taking care not to burn it.

Pour in the chicken broth, scraping the bottom of the skillet to release any brown bits. Bring to a simmer over medium heat for 2-3 minutes.

Lower heat to medium-low, stir in the heavy cream, fresh lemon juice, and lemon zest. Simmer for an additional 3-4 minutes until the sauce thickens.

Return the seared chicken breasts to the skillet and coat with the sauce. Cook together for another 2-3 minutes to meld flavors.

If desired, stir in spinach or sprinkle Parmesan cheese. Garnish with chopped parsley before serving.