01 - Preheat oven to 400°F. Position rack in the center of the oven.
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 until shimmering. Sear the chicken breasts for 3 to 4 minutes per side until a golden crust forms. Remove from the skillet and set aside on a plate.
04 - Reduce heat to medium. Add the unsalted butter to the same skillet. Once melted, 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. Cook, stirring frequently, for approximately 2 minutes until the spinach is fully wilted.
06 - Pour in the heavy cream and add the freshly grated Parmesan cheese, lemon zest, and lemon juice. Stir to combine and let the sauce simmer for 1 to 2 minutes until it slightly thickens and coats the back of a spoon.
07 - Nestle 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, or until the chicken reaches an internal temperature of 165°F when checked with a meat thermometer.
09 - Remove from the oven and let rest for 2 to 3 minutes. Serve hot, garnished with additional grated Parmesan and fresh lemon slices if desired. Pairs well with rice, pasta, or roasted potatoes.