1. Preheat oven to 250°. Place wire rack on a baking sheet and place in oven.
2. To prepare compote, heat a large nonstick skillet over medium-high heat. Coat pan with cooking spray; melt 1 tablespoon butter in pan. Add apples to pan; sauté 8 minutes or until tender. Stir in maple syrup and 1/2 teaspoon cinnamon. Keep warm.
3. To prepare French toast, combine granulated sugar and 1 teaspoon cinnamon in a medium bowl, stirring with a whisk. Add milk, vanilla, salt, and eggs; whisk until well blended. Working with 1 bread slice at a time, place bread slice into milk mixture, turning gently to coat both sides.
4. Heat a large nonstick skillet over medium-high heat. Melt 1 teaspoon butter in pan. Add 3 coated bread slices; cook 2 minutes on each side or until lightly browned. Place on rack in oven to keep warm. Repeat procedure three times with cooking spray, remaining 3 teaspoons butter, and remaining 9 coated bread slices. Serve French toast with compote. Sprinkle with powdered sugar, if desired.