2Transfer all the bread cubes to a greased 9x13 baking dish.
3In a bowl, whisk together 8 eggs, 2 cups of whole milk, 0.5 cup of sour cream, 1 teaspoon of vanilla extract, 2 teaspoons of cinnamon, and a pinch of salt.
4Pour the egg mixture on top of the bread cubes, ensuring every piece of bread gets soaked. Use a wooden spoon to dunk the bread if necessary.
5Top the bread with a can of apple pie filling, spreading it out in an even layer with the wooden spoon.
6In a small mixing bowl, combine 1 cup of all-purpose flour, 0.5 cup of light brown sugar, 0.5 cup of softened butter, and 2 teaspoons of cinnamon to make the crumbly topping.
7Mix the crumbly topping together using a fork or your hands.
8Spread the crumbly topping evenly across the top of the casserole.
9Bake in the oven at 350 degrees Fahrenheit for 45-55 minutes. (The video mentions 50 minutes).