How to make it:
Preheat the oven to 350° F.

Unfold each sheet of cold dough onto two separate sheets of parchment paper. Either roll out gently with a rolling pin or just spread out a little with your fingers. You want it to keep its rectangular shape. If it's too sticky to handle, place in the freezer for 5-10 mins.

Using a pizza cutter or a knife, slice along the fold lines and once down the long way in the center, making 6 pastries. Do for both sheets.

With one of the sheets' pieces, spread each piece apart giving them a little room to rise when baking. Slide that parchment sheet onto a baking sheet.

Dollop a few tablespoons of the jam down onto the center of those 6 pieces. Spreading just a little with the back of a spoon, but avoiding the edges. Don't use a runny jam. If it is runny, mix 1 tsp cornstarch with the jam to help thicken it.

Stab with a fork a few times in each of the jam piece's dough.

Using a clean dough piece, lay on top of the jam piece. Crimp the edges closed with a fork and stab once in the center.

Whisk an egg and 1 tsp of water together in a small bowl. Brush across the tops of each pastry. You can also just use water here but you may not achieve the shiny glow an egg wash gives. However, that won't change the pastry itself whatsoever, so it's your call.

Bake for 18-20 minutes or until the pastries have puffed up and are golden brown.

Let cool on a wire rack while you make the frosting.

In a small bowl, whisk together the powdered sugar, vanilla, milk, and about 1 tsp jam. Drizzle on each pastry when it has cooled enough to handle.

Serve warm and enjoy!