Beat cream cheese in a large bowl or stand mixer on medium speed until smooth, scrape down the sides.
Add eggs one at a time, beating between each addition, scraping down the sides as needed.
Gradually add in the eggnog and whisky.
Sift the confectioners' sugar, flour, and nutmeg together in a medium bowl, then fold it into the cream cheese mixture.
Pour filling mixture into the prepared crust.
Place springform pan in a larger baking dish and fill halfway up the pan with water.
Bake for 70 minutes.
Shut off the oven and bake for 60 additional minutes with the door closed.
Remove from the oven and transfer cheesecake to a cooling rack to cool completely.
Once cooled, transfer to the fridge to chill for 8 hours or overnight for best results.
Just before serving, whip the heavy cream, light brown sugar, and whisky until stiff peaks form.
Pipe onto cheesecake and dust with ground nutmeg.