Preheat the oven to 400 degrees F. Line a 9x13-inch baking sheet with parchment paper, set aside.
Lay out the puff pastry sheets (make sure they are cold but not frozen, being warm will be harder to handle) flat on a lightly floured surface.
Use the cookie cutter to cut Christmas tree shapes out of the puff pastry, then knead the leftover pastry dough back together. Roll it back out to about ¼-inch thickness and continue cutting out the Christmas tree shapes.
Place each of them on the prepared baking sheet. You should be able to get about 24 Christmas trees from all your dough (which will make 12 pop tarts.)
On half of the Christmas trees, place about 1 tablespoon of preserves and gently spread it out. Make sure to leave some space around the edges of the entire trees.
Top each filled tree with a plain Christmas tree cut-out and pinch the edges together slightly. Using a fork, press the seams around the edges together to completely seal.
Crack the egg in a small bowl and whisk until scrambled, then brush the egg over the tops of each pop tart.
Bake for 10-12 minutes or until they are golden brown.
Remove from the oven and allow them to cool.
While the pop tarts are cooling, in a large bowl whisk together the preserves, milk, powdered sugar and vanilla extract until combined.
Once the pop tarts have cooled and aren’t hot (if they are too hot the icing will melt off), spread the icing on top of each one.
Lastly add the sprinkles and serve.
Notes
You can use pie crust if you'd like, store bought or homemade.
Jam or jelly can be used in place of preserves and you can use your favorite flavor.
Make sure your puff pastry is thawed but is still cold when cutting out the shapes.
This makes 12 but you can easily double this recipe if you want more.