In a large bowl, place the bread cubes, raisins, apple, banana, and nuts (if using) and toss to combine.
In a medium bowl with a whisk, combine the eggs, sugar, spices, vanilla, milk, and coffee. Pour the egg mixture over the bread cube mixture and let sit 15 minutes. Pour into a 2-inch deep greased baking pan and bake for 45 minutes.
To serve, pour the Bourbon Sauce over the bread pudding. For individual servings, place large spoonfuls of the bread pudding into ovenproof dessert dishes and ladle the sauce over liberally. Place bread pudding under the broiler and broil until bubbly and caramelized.
In a mixer with a whip attachment, cream the butter and sugar together then mix in the eggs well. Transfer this to a double boiler and begin to heat it over very low heat. Stir with a wooden spoon until it is loose enough to fall from the spoon. Add the bourbon and stir in. Place the mixture in a heavy saucepan and cook it at a very, very, very low temperature for 2 hours. This maybe more sauce than you will need, but it tastes best cooked in this size.