Cube bread and spread evenly in a greased 13x9" baking pan.
In a large mixing bowl, whisk together eggs, milk, Half & Half, and vanilla.
Add in sugar and cinnamon. Mix until combined.
Pour egg mixture over bread, making sure all pieces are saturated.
Cover with plastic wrap and refrigerate overnight.
In the morning, preheat oven to 350º Fahrenheit.
Remove bake from the refrigerator and set aside.
In a small mixing bowl, whisk flour, brown sugar, cinnamon, and salt together.
Cube cold butter and cut it into the dry ingredients with a fork.
Evenly sprinkle over bread mixture.
Bake for 42-45 minutes or until center is set.