Cut the entire loaf of bread into bite-sized cubes.

Grease your baking dish and fill it with the bread cubes.

In a large bowl or measuring pitcher, whisk together the milk, heavy cream, sugar, vanilla, and eggs until well combined.

Pour this mixture evenly over the bread in the baking dish.

In a separate bowl, mix the flour, brown sugar, cinnamon, and salt.

Cut in the cold, cubed butter using a pastry cutter, fork, or your hands until the mixture is crumbly with pea-sized pieces of butter.

Sprinkle this topping evenly over the casserole.

Note: You can store the topping separately and add it right before baking, but the host recommends adding it now to save a step.

Cover the dish with foil or a lid and refrigerate overnight (or for at least several hours) to allow the bread to soak up the custard.

Preheat your oven to 350°F (175°C).

Take the casserole out of the fridge about 30 minutes before baking to take the chill off.

Uncover and bake for 45 to 60 minutes.

The casserole is done when the top is crispy and a knife inserted into the center comes out clean. (In the video, it took exactly 50 minutes).

Serve warm. It is sweet enough on its own, but you can drizzle with a little maple syrup or sprinkle with powdered sugar if desired.