Make the Dough

1. Place your butter in the freezer to keep cold before using (cut into small cubes if not done so already). Sift your flour and powdered sugar into the bowl of a stand mixer fitted with the paddle attachment, then add your salt. Mix together on low for about 30 seconds to combine.
2. Add in your cold cubes of butter, toss in the flour mixture to coat each piece, and then either flatten each piece between your fingers or beat with the mixer on low to medium-low (careful of flying flour) until the butter resembles coarse crumbs (mix of big flat pieces + small pea-sized ones). Beat in two eggs, one at a time, on medium speed until fully incorporated. Mix until the dough holds together, careful not to over-mix. Form into a disc, wrap tightly in plastic, and chill in the fridge for 1 hour.

To create some extra layers: after chilling, roll out the dough on a lightly floured surface into a large 10in. square, and fold in half twice (so it’s a quarter of the original size). Repeat the rolling and folding one more time, wrap tightly again in plastic, and chill for 1 more hour in the fridge.

Chocolate Cardamom Filling

1. While the dough chills, make the filling! Chop up your dark chocolate bars into small chunks/pieces and place in a heatproof bowl. Set aside. Pour your heavy whipping cream into a small saucepan, add in the ground cardamom, and whisk together to combine. Heat over medium heat until simmering (not boiling, shouldn’t take long).
2. Gently pour the simmering mixture over the chopped chocolate. Let rest for 3 minutes and then gently, slowly whisk the two together until smooth and the chocolate has just melted (see notes below on why you need to let it rest and whisk slowly). Set aside to cool down and thicken at room temperature for 30 minutes to 1 hour (you want it thicker, but still easy to spread).

(See notes below if your filling hardens too quickly).

Assembling & Baking

1. Prep a large baking sheet with parchment paper and set it aside. Roll out your dough on a lightly floured surface until ~1/4 inch thick, adding more flour as you go along to avoid sticking. Cut out as many 4×5 inch rectangles as you can (I can usually get about 8), then combine the scraps of dough to roll out again (adding more flour as needed) until you have 12 rectangles in total. Place on your baking sheet and chill them in the fridge for 30 minutes.
2. Lightly whisk your last egg in a small bowl for an egg wash. Brush the egg wash around the edge of half your rectangles. Scoop 1 1/2-2 tablespoons of filling into the middle, spreading into an even layer with a spoon or offset spatula. Place the other halves of your rectangles overtop those, pressing down around the edges to seal them. Crimp the edges with a fork and poke a few rows of holes in the tops of each (allows steam to escape).
3. Chill for another 30 minutes in the fridge (or 15 minutes in the freezer) while you preheat the oven to 400°F (200°C). Once chilled, brush the tops generously with the egg wash and sprinkle with the turbinado/demerara sugar. Bake for 20-25 minutes or until nice and dark. Let cool on the baking sheet for 15 minutes before transferring to a separate rack to cool completely.
4. Once fully cooled, make the glaze. Sift your powdered sugar into a small bowl, add in your whole milk by the tablespoon until desired consistency (more milk = thinner, more powdered sugar = thicker). Whisk in the ground cardamom and then spoon the glaze over your pop tarts.

These are best enjoyed same-day, but will keep at room temperate for up to 3 days stored in an airtight container (they will lose some of their initial crunch).