01 - Position the oven rack in the center and preheat the oven to 400°F (200°C).
02 - Pat the chicken breasts thoroughly dry with paper towels. Evenly season both sides with the salt, black pepper, and dried Italian herbs.
03 - Heat the olive oil in a large oven-proof skillet over medium-high heat. Sear the chicken breasts for 2 to 3 minutes per side until a golden-brown crust forms (they will finish cooking in the oven). Remove the chicken from the skillet and set it aside on a plate.
04 - Reduce the stovetop heat to medium. Melt the butter in the same skillet. Add the minced garlic and cook for approximately 30 seconds, stirring constantly until fragrant.
05 - Add the fresh spinach to the skillet and sauté, tossing gently, until the leaves are just wilted. This should take about 2 minutes.
06 - Pour the heavy cream, fresh lemon juice, and lemon zest into the skillet with the spinach. Stir the mixture well and allow it to come to a brief simmer.
07 - Sprinkle the grated Parmesan cheese into the skillet. Continue to stir until the cheese has completely melted and the sauce thickens slightly.
08 - Nestle the seared chicken breasts back into the skillet, spooning the spinach and cream sauce over the top. Transfer the entire skillet into the preheated oven. Bake for 12 to 15 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (74°C).
09 - Carefully remove the hot skillet from the oven. Serve the chicken and spinach hot, garnished with extra lemon zest or shaved Parmesan if desired.