In a mixing bowl, combine all-purpose flour, granulated sugar, and salt. Stir until mixed.

Cut in the cold unsalted butter until mixture resembles coarse crumbs.

Gradually add ice-cold water, mixing until the dough holds together. If too crumbly, add more cold water.

Shape the dough into a disk, wrap in plastic wrap, and refrigerate for about 15 minutes.

Roll out the dough on a floured surface to about 1/4-inch thickness. Cut into rectangles measuring about 3 x 4 inches.

Place half of the rectangles on a lined baking sheet. Add a tablespoon of raspberry jam in the center of each. Place the remaining rectangles on top, pressing down the edges.

Brush the tops with beaten egg.

Preheat oven to 350°F (175°C) and bake for 20-25 minutes until golden and crispy.

While the pop-tarts cool, mix powdered sugar with milk to create a drizzling icing.

Drizzle the icing over the cooled pop-tarts and add toppings if desired.