Line an 8.5" X 4.5" loaf pan with aluminum foil. Rub butter over the foil. Set aside. In a large saucepan, combine the sugar, eggnog, and corn syrup. Cook over medium heat, stirring constantly, until mixture comes to a boil.
Insert a candy thermometer into syrup mixture and cook, stirring occasionally, until thermometer registers 238 degrees (soft boil stage).
Remove the syrup from the heat and add the butter and vanilla. Stir to combine well and continue stirring until the fudge loses its shine.
Stir in the cherries and pistachios.
Transfer the fudge to the prepared loaf pan and allow to set for 4 hours before cutting.
Video
Notes
Tips and Substitutions
When using maraschino cherries, be sure to pat them dry. The wetness from the cherry can cause the fudge to loosen.
Use a candy thermometer to accurately bring the fudge to the correct temperature.
Substitute red and green candied cherries for the maraschino cherries.
Substitute slivered almonds or chopped pecans for the pistachios.
Line a bread loaf pan with tinfoil and coat the foil with butter for easy removal.