Use a paring knife to carefully cut a horizontal pocket into each chicken breast, being mindful not to cut all the way through. Gently flatten the chicken with a meat mallet to an even thickness, about 1/2 inch.
Season the inside and outside of each chicken with salt and pepper, then set aside.
Heat a skillet over medium heat and add a tablespoon of olive oil. Sauté the minced garlic until fragrant, about 30 seconds, then add chopped spinach and cook until wilted and tender, about 2 minutes. Remove from heat and let cool slightly.
In a bowl, combine the shredded cheese, chopped herbs, and sautéed spinach. Mix well to create your filling.
Spoon a generous amount of the filling into each pocket, pressing gently to pack it in. Seal the openings with toothpicks if necessary, or gently press the chicken to close.
Heat the skillet again over medium-high heat and add another tablespoon of olive oil. Sear each stuffed chicken breast for 2-3 minutes per side, until golden brown and crispy.
Transfer the seared chicken breasts to a baking dish and roast in a preheated oven at 200°C (390°F) for 20-25 minutes, or until the internal temperature reaches 74°C (165°F) and the cheese is melted and bubbly.
Remove the chicken from the oven, cover loosely with foil, and let rest for 5 minutes. This helps the juices redistribute and keeps the meat moist.
Carefully remove toothpicks if used, then slice the chicken to reveal the melty, flavorful filling inside.
Serve hot, drizzled with any pan juices or alongside your favorite side for a satisfying and mindful meal.
