Preheat oven to 350 degrees. Prepare a sheet of parchment paper over two baking pans.
Thaw pie crust according to package directions.
Roll out and cut into even strips, then cut into evenly-sized rectangles. *note: to get the scalloped edges, I used a pastry roller cutter with a scalloped edge
Place half of the rectangles onto baking sheets covered with parchment paper.
Place one lollipop stick on top of each rectangle, toward the bottom center.
Top each rectangle with a small teaspoonful of jelly. Just put enough jelly to cover the middle, leaving room around the sides; you want a little bit to ooze out of the sides, but you don't want a big globby mess when they are done baking!
Place another rectangle on top of each jellied rectangle, then gently press all sides down to seal. Use the tines of a fork to help secure the pieces together and also create a pattern around the edges.
Brush each rectangle lightly with egg wash.
Using the tips of the fork tines, gently poke a few holes at the top of each pop tart.
Bake at 350 degrees for 12-15 minutes, just until the tops are lightly brown. Allow to cool at room temperature.
Make the icing
In a medium bowl, whisk together powdered sugar and water until blended into a smooth icing consistency. If needed, slowly add more water, ½ teaspoon at a time, until you get your desired consistency.
Slowly add your choice of food coloring. I used a light purple Wilton icing coloring and it only took enough coloring to cover the bottom of a toothpick to achieve the color you see here, so start with just one drop and then add more as needed to get your desired icing color.
Spread icing over each mini pop tart.
Sprinkle immediately with colored baking sprinkles.