Grease a 9×13-inch baking dish with butter or non-stick spray.
Arrange the slices of French bread in a single layer in the prepared baking dish, slightly overlapping if needed.
In a large mixing bowl, whisk together the eggs, milk, heavy cream, granulated sugar, vanilla extract, cinnamon, and salt until fully combined.
Pour the egg mixture evenly over the bread slices, making sure all the bread is well coated. Press down gently on the bread to ensure it absorbs the liquid.
Cover the baking dish with plastic wrap or foil and refrigerate it overnight, or for at least 6-8 hours, to allow the bread to soak up the custard.
2. Make the Crème Brûlée Topping:
In a small bowl, mix together the melted butter, brown sugar, granulated sugar, vanilla extract, and cinnamon (if using). Stir until the sugar is dissolved and everything is well combined.
After the French toast has soaked overnight, remove it from the refrigerator and evenly spread the crème brûlée topping over the soaked bread.
3. Bake the French Toast:
Preheat your oven to 350°F (175°C).
Bake the French toast for 35-45 minutes, or until it is golden brown and the custard is set. The top should be slightly crisp, while the inside remains soft and creamy.
If you prefer an extra-crunchy top, you can broil it for an additional 1-2 minutes at the end (watch carefully to avoid burning).
4. Serve:
Once baked, remove the French toast from the oven and let it cool for a few minutes.
Dust with powdered sugar and garnish with fresh berries if desired.
Serve with maple syrup on the side for an extra touch of sweetness.