01 - Preheat oven to 400°F.
02 - Pat the chicken breasts dry with paper towels. Season both sides generously with salt, freshly ground black pepper, and dried Italian herbs.
03 - Heat olive oil in a large oven-safe skillet over medium-high heat. Sear the chicken breasts for 3 to 4 minutes per side until a golden crust forms. Remove from the skillet and set aside.
04 - Reduce heat to medium. Add the unsalted butter to the same skillet. Sauté the minced garlic for about 1 minute until fragrant, being careful not to let it brown.
05 - Add the fresh baby spinach to the skillet and cook, stirring frequently, for approximately 2 minutes until fully wilted.
06 - Pour in the heavy cream and add the freshly grated Parmesan cheese, lemon zest, and lemon juice. Stir well and simmer for 1 to 2 minutes until the sauce slightly thickens.
07 - Place the seared chicken breasts back into the skillet, spooning the creamy spinach sauce over the top of each piece.
08 - Transfer the skillet to the preheated oven. Bake for 12 to 15 minutes until the chicken reaches an internal temperature of 165°F and is cooked through.
09 - Serve immediately while hot, garnished with additional Parmesan cheese and fresh lemon slices if desired.