Preheat the oven to 325°F (163°C). Line a muffin tin with paper cupcake liners or grease it lightly with non-stick spray.

1. Prepare the crust: In a medium bowl, combine the graham cracker crumbs, sugar, melted butter, and cinnamon. Stir until well combined. Spoon about 1 tablespoon of the crust mixture into each muffin cup, pressing it down gently with the back of a spoon to form an even layer. Bake for 5-7 minutes, or until golden brown. Remove from the oven and set aside to cool.
2. Make the filling: In a large mixing bowl, beat the softened cream cheese and sour cream until smooth and creamy. Add the sugar, eggs, vanilla extract, and cinnamon, and beat until well combined. Mix in the flour and continue to beat until smooth. Spoon the cheesecake filling over the cooled crusts, filling each muffin cup about 3/4 full. Bake for 18-20 minutes, or until the centers are set and slightly golden. Let the cheesecakes cool in the pan for 10 minutes, then transfer them to a wire rack to cool completely. Refrigerate for at least 3 hours to allow the cheesecakes to firm up.
3. Prepare the caramel apple topping: While the cheesecakes are chilling, heat the butter in a medium skillet over medium heat. Add the diced apples and cook for about 5 minutes, until they start to soften. Add the brown sugar, cinnamon, and heavy cream, and cook for another 3-5 minutes, stirring occasionally, until the apples are tender and the sauce has thickened slightly. Remove from heat and stir in the vanilla extract and caramel sauce. Let the mixture cool to room temperature.
4. Assemble the mini cheesecakes: Once the cheesecakes have cooled and chilled, spoon a generous amount of the caramel apple topping over each cheesecake. Drizzle with additional caramel sauce, if desired.
5. Serve and enjoy: Serve the mini cheesecakes chilled, and enjoy the rich, comforting flavors of caramel apple perfection!