Prepare the Pumpkin Filling
In a mixing bowl, combine pumpkin puree, half of the egg (reserve the rest for egg wash), brown sugar, and cinnamon.
Whisk until smooth and well blended. Set aside.
Prep the Pie Crust
Preheat oven to 375°F (190°C) and line a baking sheet with parchment paper.
Unroll the refrigerated pie crusts and gently roll them out if you want thinner, crispier poptarts.
Cut the dough into small rectangles (about 3x4 inches). You should get 12 rectangles to make 6 poptarts.
Assemble the Poptarts
Lay 6 rectangles on the baking sheet.
Add 1–2 tablespoons of pumpkin filling to the center of each piece.
Brush edges lightly with the remaining egg wash.
Place another dough rectangle on top and press edges with a fork to seal.
Brush tops with egg wash for a golden crust.
Bake
Bake for 15–18 minutes, or until the poptarts are golden brown.
Allow them to cool for 10 minutes before icing.
Make the Cinnamon Icing
In a small bowl, whisk together confectioners’ sugar, vanilla extract, cinnamon, and heavy cream/milk until smooth.
Drizzle or spread icing over the cooled poptarts.