Preparing this easy yet impressive French toast casserole the night before you cook it accomplishes two important goals--not only does the overnight soak for the bread yield a creamier, fluffier result; but having everything ready to bake in the morning also lets you sleep in! Try this recipe the next time you need to feed a crowd for a special occasion breakfast or brunch. Here we use half-and-half for a very rich custard, but you can replace some or even all of it with whole milk for a lighter result. We use Granny Smiths in this recipe because they keep their shape, but other tart-firm apples will also work.