Preheat your oven to 400°F so it's ready when you need it. While the oven heats, combine the extra virgin olive oil, minced garlic, Italian seasoning, red chili flakes, sea salt, and cracked black pepper in a small bowl to create a flavorful marinade. Place the sliced chicken breast strips in a bag or bowl and coat them thoroughly with the marinade mixture, making sure each piece is evenly covered. Let the chicken sit for 10-15 minutes at room temperature to allow the flavors to penetrate the meat—this brief rest makes a noticeable difference in flavor.

Heat 1 tbsp olive oil in a large skillet over medium-high heat. Add the roughly chopped fresh spinach and cook, stirring occasionally, until completely wilted and any excess moisture has evaporated, about 3-4 minutes. This prevents the casserole from becoming watery during baking. Remove from heat and stir in the lemon juice to brighten the flavor.

Arrange the marinated chicken strips in a single layer in a 9x13 inch baking dish. Spread the softened cream cheese evenly over the chicken pieces, creating a smooth layer that will bind everything together. Top the cream cheese with the wilted spinach from Step 2, distributing it evenly across the dish. I find that spreading the cream cheese first acts as an adhesive that keeps the spinach from sliding around during baking. Finally, sprinkle the shredded mozzarella cheese over the top, followed by the grated Parmesan for a golden, flavorful crust.

Place the assembled casserole in your preheated 400°F oven and bake for 20-30 minutes, until the chicken reaches an internal temperature of 165°F when checked with a meat thermometer at the thickest point. The cheese should be melted and bubbly, with the Parmesan turning golden brown on top. Let the casserole rest for 3-5 minutes out of the oven before serving—this allows the cream cheese to set slightly and makes plating cleaner. Serve warm, and I recommend grating a little fresh Parmesan on individual portions for an extra flavor boost.