Creating Eggnog Bread Pudding With Rum Sauce is straightforward if you follow these simple steps:

1. Preheat the Oven: Begin by preheating your oven to 350°F (175°C). Grease a 9×13-inch baking dish with butter or cooking spray.
2. Prepare the Bread: In a large bowl, combine the cubed bread with raisins and nuts, if using. Set aside.
3. Mix the Custard: In another bowl, whisk together the eggnog, eggs, sugar, vanilla extract, cinnamon, nutmeg, and salt until well combined.
4. Combine Mixtures: Pour the eggnog mixture over the bread cubes. Stir gently to ensure all the bread is coated. Let it sit for about 15 minutes to absorb the liquid.
5. Transfer to Baking Dish: Pour the bread mixture into the prepared baking dish, spreading it evenly.
6. Bake: Place the dish in the preheated oven and bake for 45-50 minutes, or until the top is golden brown and a knife inserted in the center comes out clean.
7. Cool: Once baked, remove the pudding from the oven and let it cool for 10-15 minutes before serving.
8. Prepare the Rum Sauce: In a saucepan over medium heat, melt the butter. Stir in the brown sugar and continue to cook until dissolved.
9. Add Cream and Rum: Slowly whisk in the heavy cream and rum. Bring the sauce to a gentle simmer and cook for 2-3 minutes until slightly thickened. Remove from heat and stir in the vanilla extract.
10. Serve: Spoon the warm rum sauce over individual servings of the bread pudding.