1. Preheat your oven to 375°F (190°C) and line a large baking sheet with parchment paper.
2. In a large bowl, mix the flour, sugar, and salt. Add the cubed butter and use a pastry cutter or your fingers to blend until the mixture resembles coarse crumbs.
3. Gradually add ice water, a tablespoon at a time, mixing until the dough just comes together. It should be moist but not sticky.
4. Divide the dough into two equal parts. Roll out each portion on a floured surface into a rectangle about 1/4 inch thick.
5. Place one rectangle on the prepared baking sheet. Spread your chosen filling evenly, leaving a 1-inch border around the edges.
6. Place the second dough rectangle over the filling. Press the edges together with a fork to seal, then brush with the beaten egg mixed with milk.
7. Poke a few holes on top to let steam escape, and if desired, sprinkle with colorful sprinkles for that classic pop tart look.
8. Bake for 25-30 minutes or until golden brown. Let it cool slightly before slicing.

Embrace the imperfections; just like life, the beauty of homemade pastry lies in its uniqueness. This is something I learned early on—each fold and crimp tells a story.