Begin by chopping 8 ounces of white chocolate into small pieces and placing them in a microwave-safe bowl. Heat the chocolate in the microwave in 30-second intervals, stirring well after each, until fully melted and smooth. This should take about 1 to 2 minutes total.

In a large mixing bowl, combine the melted white chocolate with 4 ounces of softened cream cheese, 1 cup of powdered sugar, 1/4 teaspoon of ground nutmeg, 2 tablespoons of eggnog, and 1/2 teaspoon of vanilla extract. Blend everything together using a hand mixer until the mixture is creamy and fully combined. Once ready, cover it with plastic wrap and refrigerate for about 1 hour until firm.

Once the filling has chilled and is firm to the touch, use a cookie scoop to portion out the mixture. Roll each portion into a smooth ball with your hands, about 1 inch in diameter. Place the truffle balls on a parchment-lined baking sheet as you go to keep them organized and prevent sticking.

To ensure the truffles maintain their shape while coating, place the baking sheet with the rolled truffles in the freezer for about 10 minutes. This brief chilling will make them easier to dip in chocolate later and help them hold together nicely.

Next, melt the remaining 10 ounces of white chocolate in the microwave, again in 30-second intervals, stirring until smooth. Once melted, dip each truffle into the white chocolate, ensuring it is completely coated. Allow any excess chocolate to drip back into the bowl, then place the coated truffles back on the parchment paper.

While the coating remains wet, lightly sprinkle each truffle with additional nutmeg and, if desired, a pinch of flaky sea salt for a delightful finish. Allow the Eggnog Truffles to sit at room temperature until the chocolate coating is fully set, which may take about 30 minutes. Once hardened, transfer them to an airtight container for storage.