Spray crock pot with cooking spray, then add bread cubes and the cream cheese to the bottom of the dish
In a large mixing bowl, beat the milk with the eggs, brown sugar, vanilla and salt, pour over the bread cubes and toss to evenly coat (be gentle to not break the bread)
Place the flour sugar and butter in a large bowl and cut the butter in until evenly mixed
Sprinkle topping over the bread mixture and place lid on the pot and allow to soak overnight