01 - Preheat oven to 400°F. Position the rack in the center.
02 - In a small mixing bowl, combine the goat cheese, cream cheese, chopped basil, chives, minced garlic, and lemon zest. Season lightly with salt and pepper, then blend until smooth and well incorporated.
03 - Using a sharp knife, carefully slice a horizontal pocket into the side of each chicken breast, stopping before cutting all the way through to keep it intact.
04 - Generously fill each pocket with the cheese mixture, distributing it evenly. Secure the openings with toothpicks if needed to hold the filling in place.
05 - Season the outside of each stuffed chicken breast with salt, freshly ground black pepper, and dried thyme or herbes de Provence.
06 - Heat olive oil in a large ovenproof skillet over medium-high heat. Sear the chicken for 2 to 3 minutes per side until a golden crust forms.
07 - Transfer the skillet directly into the preheated oven. Bake for 20 to 25 minutes until the chicken is cooked through and the juices run clear.
08 - Remove from the oven and let the chicken rest for 5 minutes. Remove any toothpicks and serve hot.