Preheat the oven to 350 degrees F. Place the bread in a buttered 2 1/2-quart baking dish and set aside. Begin the custard in a small heavy-bottomed saucepan, adding 3/4 cup sugar and 1/4 cup water over low heat and stir to dissolve. Once dissolved, increase the heat to high and cook, without stirring, until the sugar has a rich caramel color, 6 to 7 minutes. Remove the caramel from the heat. Whisk in the cream and milk. Be super careful because the caramel will create steam. Add the salt, vanilla bean and seeds. Set aside.
In a small bowl, whisk the eggs for 1 minute. Ladle some of the warm caramel milk into the eggs. Whisk well to temper. With your hand, feel the bottom of the bowl and if the eggs are warm, add them to the pot with the cream. If not, add one more ladle of warm cream. Be sure to allow the cream to cool slightly before tempering in the eggs. Pour the mixture through a fine strainer over the bread cubes. Press the bread cubes into the custard making sure the bread soaks up real good. Set aside for 20 minutes unrefrigerated. Sprinkle with the turbinado sugar and place the bread pudding in a larger dish that will allow enough room for a water bath. The water should be warm or hot and come up at least 1/2 way of the bread pudding-filled dish. Bake until the pudding is set and golden brown, 35 to 40 minutes. Cool, 15 to 20 minutes.
While the bread pudding is cooling, prepare the apples by heating a saucepan for 2 to 3 minutes over medium heat. Melt the butter and add the apples. Cook, 3 to 4 minutes stirring constantly, the apples will start to brown. Add the remaining granulated sugar and cook until the apples are soft and slightly golden, 10 to 12 minutes. Add the cinnamon, toss and remove from the heat. With a slotted spoon, remove the apples and place them in a serving bowl. Add the cider to the pan and cook over high heat for 2 to 3 minutes while scraping all the delicious apple particles stuck to the pan. Add the bourbon, cook for a quick 1 minute and immediately pour over the apples. Serve the warm gooey apples over the bread pudding. I love pouring warm heavy cream over the pudding instead of the more familiar anglaise. It's fantastic!