Prepare the Crust:

Preheat Oven: Preheat your oven to 325°F (160°C). Line a muffin tin with cupcake liners or grease it lightly.

Mix Crust Ingredients: In a medium bowl, combine the graham cracker crumbs, sugar, and melted butter. Stir until the mixture resembles wet sand.

Press into Muffin Tin: Evenly distribute the crust mixture into the bottom of each muffin cup, pressing down firmly. Bake for about 5-7 minutes, then remove and let cool slightly.

Prepare the Cheesecake Filling:

Beat the Cream Cheese: In a large mixing bowl, beat the softened cream cheese until smooth and creamy.

Add Sugar and Vanilla: Gradually add the granulated sugar and vanilla extract, mixing until well combined.

Incorporate Eggs and Sour Cream: Beat in the eggs one at a time, then stir in the sour cream until the mixture is smooth.

Fill the Muffin Tins: Pour the cheesecake filling over the pre-baked crusts in the muffin tin, filling each cup about 3/4 full.

Prepare the Apple Crisp Topping:

Mix Topping Ingredients: In a medium bowl, combine the diced apples, oats, flour, brown sugar, cinnamon, and melted butter. Mix until the apples are coated and the mixture is crumbly.

Add Topping: Spoon the apple crisp topping over the cheesecake filling in each muffin cup.

Bake:

Bake: Bake in the preheated oven for 20-25 minutes, or until the cheesecake is set and the topping is golden brown.

Cool: Remove from the oven and let cool in the muffin tin for about 10 minutes, then transfer to a wire rack to cool completely.