Preheat your oven to 350°F (175°C).
Core the apples, creating a hollow center while leaving the bottom intact. Place the apples in a baking dish.
In a mixing bowl, combine the softened cream cheese, granulated sugar, vanilla extract, ground cinnamon, and salt. Beat until smooth and creamy.
Stir in the crushed graham crackers and melted butter until well combined. If using, fold in the chopped nuts.
Stuff each apple with the cheesecake mixture, packing it in gently.
Pour a little water into the bottom of the baking dish to help steam the apples while baking.
Cover the dish with aluminum foil and bake for 25 minutes.
Remove the foil and bake for an additional 10-15 minutes, or until the apples are tender and the cheesecake filling is slightly golden.
Let the apples cool for a few minutes before serving. Top with whipped cream or vanilla ice cream if desired.