Grease a 13×9 pan. Add in cubed brioche bread.
Mix together eggs, eggnog, milk, vanilla extract, brown sugar, powdered sugar, cinnamon, nutmeg, and salt. Pour mixture evenly over the bread.
Option: Cover and store in the fridge overnight. (If you do, be sure to take it out of the fridge 20-30 minutes prior to let the baking dish get to room temperature before putting it in a hot oven)
When ready to bake, preheat oven to 350°F (175°C). Combine topping ingredients and sprinkle or pour over the bread.
Bake for 40 minutes.
Once done, serve with optional toppings like maple syrup, strawberries, or powdered sugar.
Enjoy your delicious Eggnog French Toast!