The night before or at least one hour before, take the bread and arrange it into a baking dish.
In a medium mixing bowl, whisk together the eggnog, eggs, and maple syrup.
Pour this mixture evenly overtop of the bread. Cover the dish with beeswax wrap or plastic wrap and place it in the fridge.
When you are ready to bake, pull out the dish and let it sit on the counter while the oven preheats at 375℉.
In a smaller bowl, combine the cinnamon and coconut sugar. Set aside at least two teaspoons of the cinnamon sugar. Sprinkle the rest overtop of the French toast.
Bake the French toast for 40 minutes. Cover the dish if the bread browns too quickly.
To make eggnog whipped cream, whip the heavy cream, eggnog, cinnamon sugar, nutmeg, and rum extract (optional) until the cream forms stiff peaks.
Serve the French toast warm with eggnog whipped cream, powdered sugar (optional), and maple syrup. Happy holidays!
Notes
If the eggnog you are using already has a lot of eggs or sugar, you can leave out or reduce the eggs and maple syrup.