– In a large heavy skillet, combine butter and apples over medium heat. Allow butter to melt, cooking and stirring for 5 minutes. Add brown sugar, cider, cinnamon, ginger, cloves, nutmeg, and a pinch of salt. Cook and stir for 7 minutes or until the apples are tender and the sauce is thickened. Spread mixture into a 9x13 baking dish.
– In a bowl, beat eggs until foamy. Whisk in the milk, maple syrup, vanilla, cinnamon, and salt until well combined. Slowly and gently pour egg mixture over the bread slices, taking time to let the liquid soak through tops of bread to ensure even coating. Press down lightly on bread to ensure soaking. Cover dish with plastic wrap and chill 8 hours or overnight.
– Remove casserole from fridge 30 minutes before baking; meanwhile, preheat oven to 350F. Bake uncovered 35-40 minutes or just until bread tops are golden and the edges are crisp. Allow casserole to rest 10-15 minutes at room temp before cutting into it. To serve, carefully cut individual servings and invert pieces so the apples face up. Serve with maple syrup.