In a large skillet, saute spinach in 2 teaspoons oil until spinach is wilted. Add garlic; cook 1 minute longer. Remove from the heat. Stir in the spreadable cheese, 2/3 cup bread crumbs and 1/4 teaspoon salt. Cut a pocket in the thickest part of each chicken breast; fill with spinach mixture. Secure with toothpicks., Place egg in a shallow bowl. In another shallow bowl, combine the pepper and remaining bread crumbs and salt. Dip chicken in egg, then coat with bread crumb mixture., In a large skillet over medium heat, cook chicken in remaining oil for 8-10 minutes on each side or until a thermometer reads 170°. Discard toothpicks before serving.