Add flour, salt, cold butter, and sourdough discard to a blender or food processor. Blend on low until a cohesive dough forms. If it looks crumbly, you may add cool water until it creates a cohesive dough. (30-45mL)

(You can also mix the dry ingredients by hand, cut in the butter with a fork, and then stir in your sourdough discard.)

Divide dough into 2 equal pieces. Wrap and refrigerate for 2–24 hours.

If you cold-proofed your dough, take it out of the refrigerator and let it sit out for about 10 minutes. This will soften it slightly, making it easier to shape.

Now roll each piece into a large rectangle. To prevent sticking, either flour the top of your dough, or use a layer of Saran Wrapor parchment paper. For your dough that will be the top half- make sure to flour your parchment paper, so you can easily transfer the dough.

Spread strawberry preserves over one of your rectangles, leaving a ½-inch border around the edges. Poke a few holes on the second rectangle with a fork to let steam escape. Place it over the strawberry-covered bottom crust.

(Note: If your dough seems sticky when trying to transfer, go ahead and pop it in the fridge and let it harden up again before transferring to the bottom crust.)

Press the edges of the two rectangles together, and crimp with a fork.

Whisk 1 egg + 1 tbsp water together and brush over the top of your pop tart. The egg wash is optional, but it gives your crust a nice, glossy appearance when baked.

Bake your massive pop tart at 350°F for 35–40 minutes, until golden brown around the edges. Allow to cool.

Step Seven: Frost

Combine powdered sugar and milk to make the frosting. Spread the frosting generously over the top of your pop tart, and add sprinkles to taste. Let cool and enjoy!