In a medium saucepan over medium heat, combine the finely diced tart apples, brown sugar, cornstarch, ground cinnamon, and water. Cook for about 10–12 minutes, stirring occasionally, until the apples are tender and most of the liquid has evaporated. Once done, remove from heat and allow the apple compote to cool completely before using it to fill your Apple Pie Cupcakes.

Preheat your oven to 350°F (175°C), ensuring it's properly heated for even baking. Meanwhile, line a cupcake pan with cupcake liners to prevent sticking and make cleanup easier.

In a large mixing bowl, whisk together the cake flour, baking powder, additional ground cinnamon, and salt until evenly combined. Set the bowl aside while you work on the wet ingredients.

In another bowl, cream the softened unsalted butter until light and fluffy, about 2-3 minutes. Gradually add the granulated sugar, continuing to beat for an additional 2 minutes. Incorporate the eggs, one at a time, mixing well after each addition, and then stir in the vanilla extract.

Gently fold the dry ingredients into the wet mixture, alternating with the milk. Mix just until everything is combined and smooth.

Using a scoop or spoon, fill each cupcake liner about two-thirds full with batter.

Place the filled cupcake pan in the preheated oven and bake for 18–20 minutes, or until a toothpick inserted into the center comes out clean. Allow the cupcakes to cool in the pan for 5 minutes before transferring them to a wire rack to cool completely.

In a mixing bowl, beat the softened cream cheese and remaining butter until smooth and creamy. Gradually add the powdered sugar, cinnamon, and vanilla extract, mixing until well combined.

Once the cupcakes are completely cooled, fill the center with the cooled apple compote, then generously pipe the frosting on top.