• Line a 12x18-inch rimmed baking sheet (cookie sheet) with parchment paper. Set aside.

Strawberry Filling

• Add the strawberry preserves to a small saucepan.
  1 cup strawberry preserves
• In a small bowl, whisk together the cornstarch and water until smooth. Stir the cornstarch mixture into the cold strawberry preserves in the saucepan.
  1 teaspoon cornstarch, 1 teaspoon water
• Cook the strawberry preserves mixture over medium-low heat, on the stove top, for 2 to 3 minutes while stirring often. The mixture should be bubbling and slightly thickened.
• Transfer the strawberry filling to a bowl and let it cool at room temperature for 10 minutes.

Pop-Tart Crust

• Unroll one of the pie crusts onto a separate sheet of parchment paper. Use a rolling pin to shape it into an approximately 9x12-inch rectangle, trimming any uneven edges as needed. Transfer the crust (and parchment paper) to the prepared sheet pan.
  1 package (14.1 oz) refrigerated pie crusts
• Whisk together the large egg and water in a small bowl. Set the egg wash aside.
  1 large egg, 1 teaspoon water
• Spread the cooled strawberry filling evenly over the bottom crust, making sure to leave a ¾-inch border around the edges. Lightly brush the exposed border with some of the egg wash.
• Unroll the second refrigerated pie crust and roll it into the same size (9x12-inch rectangle). Carefully place it over the strawberry filling and gently press the edges of the two pie crusts together.
• Use a fork to crimp the edges and seal the pop tart. Then use the same fork to prick the top crust several times, which allows steam to escape while baking.
• Refrigerate the assembled pop tart (unbaked) for 15 minutes. Preheat the oven to 425°F while the pop tart chills.

Bake & Cool

• Brush the chilled top crust evenly with the remaining egg wash.
• Bake for 16-20 minutes or until the crust is deeply golden brown and the edges feel firm.
• Remove the pop tart from the oven and allow it cool on the warm sheet pan for 10 minutes.
• Carefully transfer it, with the parchment paper, onto a wire rack and let it cool completely for about 25 minutes.

Glaze

• In a bowl, whisk together the powdered sugar, whole milk, and vanilla extract until smooth and thick but still spreadable. Add additional milk, 1 teaspoon at a time, only if the glaze is too thick.
  1½ cups powdered sugar, 2 tablespoons whole milk, ½ teaspoon pure vanilla extract
• Spread the glaze over the cooled pop tart, leaving a small border around the edges. Immediately top it with the sprinkles and let the glaze set for 20 to 30 minutes before cutting and eating.
  rainbow sprinkles
• Cut the strawberry pop tart into 12 square pieces and serve. Enjoy!