Line a 13x9-inch baking dish with parchment paper. Set aside. Preheat oven to 350 degrees.
In a food processor, pulse gingersnap cookies until fine crumbs. Add in melted butter and pulse until combined.
Press crumbs into the bottom of prepared baking dish. Using the palm of your hand (or bottom of a cup) press crumbs firmly into the pan.
For the cheesecake filling, beat cream cheese with sugar, eggs, rum extract and nutmeg using the whisk attachment of your electric mixer. Beat until fluffy and smooth (about 3-4 minutes). Pour over gingersnap crust.
For the cookie layer, beat butter with sugar for 2 minutes. Add egg and vanilla and beat thoroughly. Add in baking powder, salt, flour, cinnamon and nutmeg and beat until fully combined. Add milk and beat until well blended. Scoop dough by large spoonfuls onto the top of the cheesecake layer. Use your fingertips to spread gently until the cheesecake layer is fully covered.
In a small bowl, combine the topping ingredients. Sprinkle generously over the cookie layer.
Bake for about 35 minutes. Middle may still "jiggle", that's okay. You want the cookie layer to be completely cooked (and lightly browned). Remove from oven and cool completely. Once cooled, cover with foil or plastic wrap and refrigerate for 4 hours (or overnight). Cut into squares and enjoy cold!
Notes
You should store these in the refrigerator for freshness and best taste. I love them chilled straight from the fridge!
If you omit the rum extract you won’t get the name eggnog flavor. Rum extract is worth the purchase! After you make cheesecake bars, use it in Eggnog Fudge, Butter Rum Fudge and Homemade Eggnog.
The cheesecake bars are ready to come out of the oven when the cookie crust is lightly browned. The center of the cheesecake may be slightly jiggly but it will continue to firm as it cools (and when it’s chilled).