Preheat your oven to 350°F (175°C) and spray a 9x13-inch baking dish with non-stick spray.

Slice day-old French bread into 1-2 inch cubes and place them in a large mixing bowl.

In a separate bowl, whisk together eggs, sugar, milk, heavy cream, vanilla, cinnamon, and nutmeg until smooth.

Pour the custard mixture over the cubed bread, stir gently, and let it soak for 20 minutes.

Transfer the soaked bread mixture into the prepared baking dish and bake for 50-60 minutes until set.

In a saucepan, whisk together sugar, flour, and heavy cream over medium heat until thickened, then stir in butter and vanilla.