Pre-heat oven to 350.
First, add the dry ingredients to a food processor and pulse until well mixed.
Next, add the butter and pulse until the butter breaks down to pea size.
Now, add the egg yolk and pulse until combined and the dough is starting to come together.
Line a large sheet pan with a sheet of parchment paper. Turn the dough out onto the sheet pan and press the dough until it fills the pan completely and is the same thickness throughout. This way, you don’t have to measure, the sheet pan does that for you to create a perfect rectangle.
Then, you are going to cut a line horizontally down the middle of the dough. This will be your dividing line, creating a top dough and a bottom dough.
On one side of the cut, spread the jelly/jam, leaving about a ½ inch border all the way around. Now, you are going to flip the side of the dough without jelly, directly on top of the side with jelly. Viola!
Place in the oven and bake for 22-25 minutes, until lightly golden brown.
While the pop tart is baking, mix up the frosting. Add all frosting ingredients to a small bowl and whisk until smooth. The addition of the reserved jelly/jam to the frosting is my hack that I have fallen in love with. It adds beautiful color and extends the flavor of the pop tart.
Once the pop tart is completely cooled, spread the frosting on top. Let the frosting set, then cut into individual squares. Enjoy!