Process the Biscoff cookies in the bowl of the food processor until you have crumbs. Pulse while drizzling in the melted butter. Press into the bottom and about 1 inch up the side of the cheesecake pan. Bake in the preheated oven for 7 to 8 minutes, then remove and allow to cool.
In the mixing bowl, mix the softened cream cheese, adding each egg one at a time, until thoroughly combined. Add the sugar, vanilla, and ground nutmeg, mixing thoroughly. Slowly add the eggnog ⅓ cup at a time, mixing between each addition. Slowly add the Myer’s Dark Rum, and mix until everything is thoroughly combined and satin smooth.
Pour the mixture into the cheesecake pan, then place it into the middle of the large roasting pan. Pour hot water around the cheesecake pan until it’s about halfway up the sides. Bake until the cake is almost set in the middle, but still has a small wobbly area in the center about 2 inches in diameter, about 60 to 75 minutes. Remove from the oven and allow to cool completely on a wire rack. Chill in the refrigerator overnight, and keep cold until ready to serve.