• Preheat oven to 350℉.
• Place two of the store bought pie crusts on a piece of parchment paper.
• Make a rectangle (or as close as you can) with the pie crusts, overlapping if necessary and using a rolling pin.
• In a small bowl, mix together the brown sugar, cinnamon and flour mixture.
• Spread the brown sugar mixture on the pie crusts.
• Cover the brown sugar mixture with the remaining two pie crusts.
• Trim the sides of the pastry with a dough cutter if desired to make it clean and shaped like a rectangle.
• Bake for 20 minutes or until Pop Tarts are lightly brown and dough is cooked.

For The Frosting

• Whisk together the powdered sugar, cinnamon, butter and water in bowl.
• Add more powdered sugar if desired for thicker consistency.
• When Pop Tarts have cooled, spread on top of the Pop Tarts and let the frosting set up.
• Serve.