Mix all the ingredients for the filling in a small casserole. Bring to boil and simmer for 3 minutes, until the apples become tender. Let the filling cool down for a few minutes and then transfer into the fridge to cool down completely.
In a bowl, mix all the ingredients for the dough until a cohesive ball is formed. Refrigerate for 30 minutes.
Preheat the oven to 350°F.
Once the dough is ready, transfer it on a floured surface. Roll it out to form a long rectangle about 0.5 cm thick. Cut the edges to straighten the rectangle. Keep the scraps aside, you will reuse them.
Cut long stripes about 7 x 22 cm. Add 1 1/2 tbsp of filling on the middle of the top half of each stripe. Fold the bottom part over and close the edges by pressing them with a fork.
Transfer on a baking sheet covered with parchment paper.
Bake for 25-30 minutes, until the edges become golden-brown. Transfer on a cooling tray and allow to cool down for a few minutes.
In the meanwhile, prepare the glazing by mixing the butterscotch chips and the milk in a small bowl. Melt by microwaving in 30 seconds intervals, mixing in between.
Swirl over the pop tarts and enjoy!