Start by lining your 9x9 pan with parchment paper. This helps keep the fudge from sticking, and it’ll be easier to remove when it’s set.
In a medium saucepan, combine your sugar, eggnog, and heavy cream. Stir occasionally as you bring the mixture to a boil over medium heat. Keep an eye on it, as it will start thickening up.
Once the mixture starts to boil, reduce the heat slightly and continue stirring for about 10 minutes. You want to make sure the mixture thickens but doesn’t burn, so constant stirring is key.
Now, turn the heat to low. Add in your white chocolate chips and marshmallow creme. Stir until everything is melted and combined into a smooth mixture.
Pour the fudge mixture into your prepared 9x9 pan, spreading it out evenly. Then, sprinkle the nutmeg over the top for a light spiced finish.
Allow the fudge to cool at room temperature for at least an hour, or refrigerate it if you’re in a hurry. Once it’s set, you’ll be able to cut it into squares.
Once your fudge has set, you can store it in an airtight container, or just enjoy it right away. It’s perfect for snacking, gifting, or sharing with friends.