In a medium-sized saucepan, bring the sugar, butter and eggnog to a full boil over medium-heat for about 4 minutes. Stir constantly to prevent scorching.
Continue to cook over medium until a candy thermometer reaches 234°F.
Remove from heat and stir in the white chocolate and nutmeg. Stir until the chocolate is melted. Then immediately stir in the marshmallow creme and vanilla extract. Use a mixer with whisk attachment to beat until well blended.
Pour into a buttered 8x8" square pan. Sprinkle extra nutmeg on top.
Cool in the refrigerator, then cut into squares.
Storage:Store in an airtight container in the refrigerator for up to one week. To freeze, wrap in foil and then place in the freezer for up to 3 months.Eggnog: Make sure to use a full fat eggnog (don't use a light version, or it will separate). My favorite brand is Darigold.