Chop the butter into small chunks and place in a small bowl. Put the butter, shortening, and water into the freezer for about 5 minutes or until really cold.

Add the gluten-free flour, sugar, salt in a large bowl and stir to combine the ingredients.

Add the butter and shortening to the flour mixture and mix until the butter and shortening are incorporated into the flour.

Add in the eggs, water and apple cider vinegar and mix until the dough starts to form and all the ingredients are combined. The dough will be sticky.

Shape the dough into a ball, wrap in plastic wrap and refrigerate for at least 45 minutes.

Preheat your oven to 350°F (177°C).

Unwrap the dough ball, cut the dough ball in half and place the half onto parchment paper lightly floured with gluten-free flour.

Shape the dough half into a rectangle. Lightly flour the pastry with gluten-free flour, and using a rolling pin, roll out the dough to about ¼-inch thick.

Using a pizza cutter, cut the 9-inch by 8-inch rectangle. Cut out the dough into 3-inch by 4-inch rectangles.

Place the dough rectangles onto a parchment-lined baking sheet.

Repeat the steps with the other half of the dough ball to make 8 more rectangles.

Spread 2 teaspoons of seedless jam of the top of each dough rectangle.

Place the dough rectangles on top of the filling-topped dough rectangles.

Use a fork to crimp the sides of the dough together.

Use a fork to poke the tops of the pop tarts 3 times.

In a small bowl whisk together the egg and stir in the water. Brush egg wash on the tops of the pop tarts.

Bake for 20-25 minutes until the pastries are golden and browning on the edges.

Let the baked pop tarts cool on the pan for 5 minutes, then transfer to a wire rack to cool completely before glazing.

In a small bowl whisk together the ingredients for the glaze until smooth.

Use a spoon or small spatula to glaze each pop tart. The glaze will slightly harden.

Store pop tarts in an airtight container at room temperature for 3 days or in the refrigerator for 6 days.