Make the Pop-Tarts. Unroll thawed pie crust and use halloween cookie cutters of your choice to cut 24 shapes out of the dough. Place 1 to 2 tablespoons of jam on just half of the pie cut-outs.
Whisk an egg in a small bowl with 1 teaspoon of water. Brush the outer edges of the pie cut-outs topped with jam and cover with the remaining 12 cut outs. Use the tines of a fork to seal edges and poke holes in the center of each so they can release steam without becoming too puffed.
Bake for 8 to 10 minutes, or until Pop-Tarts are golden brown. Remove and let cool.
Make the icing. Combine confectioners sugar, egg white, and water in a small mixing bowl and whisk together until well combined. If you want to change the color of the icing, just add a few drops of food coloring and stir again.
Once the Pop-Tarts have cooled, ice away. Top each pastry with candy googly eyes for fun.