Creating the perfect Bananas Foster French Toast Casserole is simple if you follow these clear steps:

1. Prepare the Bread: Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish. Place the bread cubes evenly in the dish.
2. Make the Custard: In a large bowl, whisk together the eggs, milk, heavy cream, granulated sugar, vanilla extract, cinnamon, and salt until well combined.
3. Pour Over Bread: Pour the custard mixture over the bread cubes, ensuring all pieces are soaked. Press down gently to make sure the bread absorbs the liquid.
4. Add Bananas: Layer the sliced bananas on top of the bread mixture.
5. Prepare the Topping: In a small saucepan, melt the butter and brown sugar over medium heat. Stir until combined and slightly thickened. If using rum, add it now and mix well.
6. Drizzle the Topping: Pour the butter and brown sugar mixture evenly over the bananas and bread.
7. Bake: Cover the dish with aluminum foil and bake for 30 minutes. Then, remove the foil and bake for an additional 15-20 minutes, or until the top is golden brown and the casserole is set.