Preheat oven to 350.
Line a baking sheet with parchment paper.
Chop the apple into tiny pieces and toss it with cinnamon.
In a medium bowl, whisk together the water, oil, and vanilla.
Then add the flour.
Mix until a dough ball forms.
Use your hands and press the dough into a rectangle shape (the dough shouldn’t be sticky!).
Fill one side with the apple mixture.
Fold the other side over.
Use a fork to crimp the edges.
Bake for 20 minutes.
Let cool completely.
Next, make the frosting, whisking together the powdered sugar and water until all the chunks are gone. You might need to adjust by adding more sugar or more water.
Glaze your pop tart, add sprinkles and eat!