Soak the bread in the egg mixture and jam (or apple butter) the night before, and add the crunchy topping the morning of, before placing in the oven to bake! Perfect make-ahead breakfast to serve to out-of-town guests.
The night before, assemble the French toast. Prepare a 9×13 pan by lightly spraying the sides and bottom.
Mix the eggs, milk, apple juice, vanilla, and salt. Set aside.
Spread a thin layer of the preserves on one side of each slice of bread, and then dip into the egg mixture. Arrange the slices jam side up in the baking dish, overlapping slightly if necessary. Pour any remaining egg mixture over the bread and gently press the bread into the custard. Cover tightly with foil and refrigerate for 4-18 hours.
In a large bowl, combine the butter, oats, brown sugar, cinnamon, vanilla, salt, and nuts. Cover the bowl and refrigerate until ready to bake the French toast.
In the morning, preheat the oven to 350 degrees. Uncover the egg/bread mixture and press down on the bread to absorb any custard on the bottom of the dish. Scatter the topping on the dish, sprinkle with cranberries, recover with foil, and bake for 30 minutes. Remove the foil and bake for another 15-20 minutes, until puffy and golden brown. Let cool for 10 minutes before serving.
Serve with syrup, powdered sugar, or more preserves.