S'mores Pop Tarts

1.) Cut cold butter into 1/2" cubes. 2.) Put graham crackers in a gallon freezer bag. Roll with a rolling pin until fine and uniform. Makes 1 1/4 cup. 3.) Whisk and combine graham cracker crumbs, flour, and salt in a large bowl. 4.) Put cubed butter into the mixture and toss with fingers to coat all sides of the butter. 5.) Using a pastry blender, cut in the butter until reduced to pea-sized pieces. You can also use your hands. 6.) Whisk egg yolks and milk in a small bowl until combined. 7.) Combine the egg mixture and flour mixture with your hands until a sticky dough forms. 8.) Cut the dough into 2 equal parts and shape into rectangles. 9.) Cover with plastic wrap and refrigerate for 1 1/2 hours. 10.) Preheat oven to 375° and line a baking sheet with parchment. Roll the first rectangle into a 12x10-inch rectangle. Cut into 6 smaller rectangles (3 1/2 x 4 1/2). Place all 6 on parchment and put in fridge. 11.) Roll out 2nd rectangle into the same dimensions as the first, cut into 6 rectangles. Whisk water and egg in a small bowl and brush a thin layer over chilled rectangles. 12.) Scoop 2 tablespoons of marshmallow creme on chilled rectangle. Sprinkle a pinch of chopped dark chocolate. 13.) Place a nonchilled rectangle over the marshmallow creme. Press on the edges to stick the 2 together, press lightly on tops of pop tart to flatten. Dip a for in flour then crimp the edges of the tart. 14.) Poke the tops of the tarts with the tip of the fork 3 times, giving 12 holes total in the center. 15.) Bake in oven until golden brown and the marshmallow has puffed. Cool on sheet for 5 minutes then on a wire rack to cool completely. Melt chocolate and drizzle over the tops with a pastry bag or spoon.