In a large bowl, whisk together eggs, milk, cinnamon, orange zest and vanilla. Dip bread slices into egg mixture and place in a lightly greased 9X13 inch baking pan. Pour the remaining egg mixture over the bread and refrigerate overnight.
In the morning
Preheat oven to 350°F / 175°C.
In a small bowl, combine butter, light brown sugar, orange zest, orange juice, maple syrup and pecans. Spread mixture over bread.
Bake in a preheated oven until golden, about 40-50 minutes. Let stand 5 minutes before serving.