Preheat the oven to 350F and line a standard muffin pan with paper liners. 

In a small bowl, mix together the graham cracker crumbs and sugar. Add the butter and mix until the crust resembles wet sand. 

Add a heaping tablespoon to the bottom of each well in the muffin pan and press the crust into a compact layer. Set aside until ready to use. 

Add the cream cheese, sugar, flour, and vanilla to a large bowl (or the bowl of a stand mixer fitted with the paddle attachment). 

Beat on medium speed for 2-3 minutes or until the mixture is light and fluffy. Add the eggs one at a time, mixing well after each addition. Make sure to scrape down the sides of the bowl as needed. 

Divide the cheesecake mixture between the wells of the muffin pan, filling each one about ¾ of the way full. 

Set aside while you make the apple crisp layer. 

In a medium bowl, combine the diced apples, granulated sugar, lemon juice, cornstarch, and cinnamon. 

Add a heaping tablespoon of the apple mixture to the top of each cheesecake layer. 

In a small bowl, stir together the flour, brown sugar, and oats. Add the melted butter and stir until a crumble forms. 

Top each apple layer with about 2 teaspoons of the oat crumble. 

Bake the cheesecakes for 38-40 minutes or until the crisp layer is golden brown on top. 

Allow the cheesecakes to cool completely at room temperature in the pan. Then transfer the pan to the fridge and chill for at least 4 hours before enjoying.