1. Preheat oven to 350°.
2. Combine milk, brown sugar, granulated sugar, vanilla, cinnamon, nutmeg, salt, and eggs in a medium bowl, stirring with a whisk.
3. Place cubed bread in an 11 x 7-inch baking dish coated with cooking spray; sprinkle raisins over bread. Pour egg mixture over bread. Press down lightly on bread, using a spatula, allowing bread to absorb egg mixture. Cover and chill 1 hour.
4. Place baking dish in a large roasting pan; add enough hot water to roasting pan to come halfway up sides of baking dish. Bake at 350° for 1 hour or until center of pudding appears set. Cool 20 minutes in pan. Serve with caramel syrup.