Melt the butter and pour into the casserole. Stir in the brown sugar, cinnamon, nutmeg, nuts (optional), orange zest, and 2 tablespoons of the orange juice. Press along the bottom to form a kind of crust.
Arrange the apples and cranberries over the butter and sugar mixture.
Arrange the bread slices in a way that covers the fruit. Drizzle half the remaining orange juice over the bread.
Whisk together the beaten eggs and half & half, and pour half of it over the bread.
Make another layer of bread, drizzle remaining orange juice and then pour on the remaining egg mixture.
Cover with plastic wrap and refrigerate overnight.
Preheat oven to 375° F/190° C. Remove plastic wrap, cover with foil, and bake for approximately 40 minutes. Remove the foil for the last few minutes of cooking to brown and crisp the top layer of bread. Scoop out large spoonfuls and turn over onto serving plates.
Prep Time does not include overnight time in the refrigerator.