If using leftover meat, measure and go to step 2. If using fresh turkey or chicken, slice turkey or chicken in half horizontally, creating thin cutlets. Heat ½ tbsp oil in a skillet over med high heat. Season chicken with salt and pepper and sauté for 5 min or until no longer pink in center. Remove and reserve on plate.
In shallow dish, whisk egg, milk, nutmeg and cinnamon together until blended. Spread cranberry sauce or mustard on one side of each slice of bread and place sauce side up on work surface. Layer 2 slices with a piece of cheese, spinach, pear or apple, turkey or chicken and another piece of cheese, Top with remaining slice of bread, sauce side down. Gently press together. You should now have 2 sandwiches.
Heat remaining oil in the skillet over med high heat and use a wide spatula to carefully dip each sandwich into the egg mix, coating both sides. You can help it along with a brush if you would like to or if you feel that you need more egg mixture, double up on the milk, eggs, nutmeg and cinnamon as well. Place in hot skillet. Saute turning once in about 5 minutes or until golden brown. Remove from heat and cut sandwich on an angle. Arrange the sandwiches on a plate and dust with 1 tbsp of powdered sugar each. If you wish, you can have extra sauce on the side for dipping or spreading onto sandwich.