Lightly mist a 9x13 dish with baking spray. Layer the bread slices, overlapping if necessary. Set aside for later.
Place the sugar and scraped inside of the vanilla bean into a small bowl. Whisk together until fragrant, roughly 15 to 20 seconds. Set aside.
In a large bowl, whisk the eggs until lightly foamy, about 10 seconds. Add the cream, orange juice, salt, and 3/4 cup of the vanilla sugar.
Pour the custard mixture over the top of the bread inside the pan. Let soak for 15 minutes then turn each bread piece.
Cover tightly and refrigerate overnight, or at least 4-5 hours.
When ready to bake, remove the pan from the refrigerator and allow to sit at room temperature for 20 minutes. Remove the cover.
Preheat the oven to 350 degrees. Sprinkle the remaining 1/4 up vanilla sugar over the bread and bake 45-55 minutes, or until lightly golden browned and cooked through.