1. Preheat the oven to 325°F and line a muffin tin with 12 cupcake liners.

2. In a bowl, combine graham cracker crumbs and melted butter. Press a tablespoon into the bottom of each liner. Bake for 5 minutes and let cool.

3. In a mixing bowl, beat the cream cheese until smooth. Add granulated sugar, egg, and vanilla. Beat until creamy and fully combined. Spoon over each crust.

4. In a small skillet, sauté diced apples with cinnamon and 2 tablespoons of brown sugar for 5 minutes until softened. Let cool slightly and spoon over cheesecake layer.

5. In a separate bowl, mix oats, flour, 1/3 cup brown sugar, and cold butter. Use fingers or pastry cutter to form a crumbly texture. Sprinkle over each cheesecake.

6. Bake for 18 to 22 minutes, until centers are just set. Cool at room temperature, then refrigerate for at least 2 hours before serving.