1. The day before, generously butter a deep 2-qt baking dish. Line the bottom and sides of the dish with some of the bread slices, starting with the bottom and cutting and trimming the slices as needed. Leave a little edge of bread extending above the rim of the dish to support the pudding as it puffs.
2. In a mixing bowl, whisk together the eggs, milk, 1/2 cup of the sugar, and the vanilla.
3. Pour half of the milk mixture into the bread-lined dish.
4. Top with a layer of the apple slices and the raisins (if using), and then a layer of bread slices. Repeat until the dish is filled, ending with a layer of bread.
5. Set the dish on a plate to catch any overflow, then pour the remaining milk mixture over the top.
6. In a small bowl, stir together the cinnamon, nutmeg and the remaining 1/2 cup sugar. Sprinkle the mixture over the top, then dot with the butter.
7. Cover and refrigerate until the bread absorbs the liquid, 6 – 8 hours or for up to overnight.
8. Preheat the oven to 350°.
9. Bake,uncovered, until the top is browned and a knife inserted into the center comes out clean, 45 minutes – 1 hour.
10. Whip the cream just until it starts to thicken.
11. Serve warm on individual plates. Spoon some of the cream over each serving.