In a large bowl, with a pastry cutter, gradually work the butter into the flour + white whole wheat flour until it resembles coarse meal. In a small bowl, beat the egg with a fork and then pour it into the flour and butter mixture. Add 5 tablespoons of cold water, 1 tablespoon of apple cider vinegar and 1 teaspoon of salt. Stir together gently until all of the ingredients are incorporated and the dough forms a ball.

Separate the dough ball into thirds. Form 3 evenly sized balls of dough and place each dough into a large Ziploc bag or wrap with plastic wrap. Using a rolling pin or your hands, slightly flatten each ball of dough to make rolling easier later. Seal the bags and place them in the fridge for 30 minutes or until you are ready to roll the dough out.

Preheat the oven to 350 degrees F.

In a bowl beat together the pumpkin, egg, brown sugar, cinnamon, ginger, nutmeg, salt and milk until smooth.

On a floured surface, roll the dough out into an 1/8-inch thickness. Cut the dough into rectangles, roughly about 6 1/2 x 4 1/2 inches. Place a heaping tablespoon of the pumpkin filling on one of the rectangles, smoothing the pumpkin out to just before the edge of the dough. Drizzle the melted Nutella over the pumpkin and use a toothpick or knife to lightly swirl the Nutella into the pumpkin. Lay the another rectangle of dough over the filling and seal the edges by crimping with the back of a fork. Repeat until all the dough has been used, saving the scraps and re-rolling to make more rectangles. Bake the pop tarts for 20 to 25 minutes. Cool completely

While the pop-tarts cool make the frosting. Brown the butter on the stove and then whisk in the powdered sugar, maple syrup and vanilla. If needed, whisk in the milk to thin. If the frosting seems too thin, add 1 tablespoon powdered sugar at a time until the frosting is thick, but pourable.

Drizzle the glaze over the cooled pop-tarts and sprinkle generously with cinnamon sugar. The glaze will harden after 5-10 minutes.

Store in an airtight container for up to 4-6 days in the fridge. If desired these can be heated in a 350 degree oven for 3-5 minutes to warm them before eating, BUT the glaze will melt slightly on the pop-tart.