Put all the ingredients for the crust into a bowl and mix well until combined to form a dough. Put in fridge for 4-6 hours.
Preheat oven to 350 degrees F.
Take the dough out of the fridge and you'll want to leave it at room temperature for a couple minutes as this will make it easier to work with.
Put the ball of dough in-between two sheets of parchment paper. Use a roller to flatten out the dough. The thinner you make the dough, the more it will break. I like to keep it a little thick, so it doesn't fall apart. This might be trial and error for you in the first batch.
Once flattened out, use a ruler to measure the sides to create perfect rectangles. I went with 5x4 inches. Use a knife to cut those measurements.
Place the first rectangle on a baking sheet lined with parchment paper. Take a spoonful of jelly and put on top of that rectangle. Go back to your dough and cut another rectangle and place it on top of the jelly.
Take a fork and slightly smash the sides together. You'll have that little imprint from the fork around the sides.
Repeat until all poptarts are done. You will have to ball up the dough, re-flatten, measure and cut.
Bake for 20 minutes.
Take out of the oven and enjoy! :)