• In a large bowl, whisk together flour, cocoa powder, sugar, and salt.
• Add cubed butter to flour mixture and, using a pastry cutter or your fingers, cut the butter in until the mixture resembles fine crumbs.
• In a separate medium bowl, stir together egg, buttermilk, vinegar, and red food coloring.
• Add wet ingredients to bowl with dry ingredients and use a wooden spoon, a spatula, or your hands to combine. I like to use my hands, but they do turn a little red from the dye. Knead it gently in the bowl until the dough comes together (If you really don't want to touch it due to the red dye, you can put it in a stand mixer and use the dough hook to knead it together).
• Divide dough into two equal-sized balls Wrap each with plastic wrap, press gently into discs, and refrigerate for about an hour.
• Preheat oven to 375 degrees and line two large baking sheets with parchment paper.
• On a lightly floured surface, roll one of your pastry discs out until it's about ⅛" thick. Use a cookie cutter to cut out hearts (or desired shapes) and set cut-outs on prepared baking sheet. Re-roll dough and continue to cut. Repeat with second portion of dough.
• Brush edges of dough with a little bit of buttermilk and add a small scoop of cream cheese filling onto half of the hearts, being sure to leave a little bit of space around the edges.
• Place a second dough heart on top of the cream cheese topped ones and, using your fingers, press down around the seams to seal them tight. Press the tines of a fork around the edges of each of the hearts and prick the tops multiple times to allow steam to escape. Brush the tops of the Pop Tarts with more buttermilk.
• Bake for about 20-24 minutes, until tarts are cooked through and getting crispy. Remove and cool on metal racks.
• Top each of the cooled Pop Tart with icing. You can either just drizzle it on or try to keep it in a heart-shape. Add sprinkles.

Cream Cheese Filling

• In the bowl of a stand mixer or in a large bowl with a hand mixer, beat together cream cheese, confectioners' sugar, vanilla, and salt until smooth, 3-4 minutes.

Vanilla Icing

• In a medium bowl, whisk together confectioners' sugar, 1 ½ Tbsp buttermilk, and vanilla, until smooth. If icing is too thick, add remaining ½ Tbsp buttermilk.