Roll out the puff pastry on a floured surface until ¼ - ½ inch thick.
With a pizza cutter or knife cut your pastry to 3inch x 4inch rectangles. You will need 2 for each Pop-Tart.
On one piece of pastry, lay on some ham and sprinkle over grated cheese. Take care not to overfill or the filling will come out.
Egg wash the edges of the pastry around the filling, lay on the top layer and seal the 2 pieces together with a fork. Egg wash the top of the Pop-Tart, this will give it a lovely golden color. Prick the top with a fork to release steam while baking.
Bake at 400oF (200oC) for 20-23 minutes or until golden brown.
Enjoy warm from the oven.
You can freeze the Pop-Tarts raw and then bake from frozen when needed.
Egg wash: whisk up an egg yolk with 4 tablespoons of milk and brush over pastry