Preheat your oven to 350°F (175°C).
Grease the 9x13 inch baking dish with butter or non-stick spray.
Cut the bread into 1-inch cubes and place them in the greased baking dish evenly.
In a mixing bowl, whisk together the eggs, milk, heavy cream, sugar, vanilla extract, cinnamon, and salt until smooth and well combined.
Pour the egg mixture evenly over the bread cubes, gently pressing down with a fork to help the bread soak up the custard.
Cover the dish with aluminum foil and let it sit for 15 minutes or overnight in the refrigerator.
Bake in the preheated oven for 30 minutes covered with foil.
Remove the foil and bake for an additional 15 minutes, or until the top is golden and the casserole is set.
Remove from the oven and let it cool for a few minutes.
Drizzle with maple syrup and dust with powdered sugar if desired before serving.