• Make your mashed potatoes with 3-4 large potatoes. Make sure to keep 1 cup of the potato cooking water, after they have boiled.

Make the Pie Dough

• In a large bowl, measure out the flour and the salt. Mix to combine.
• Blend the shortening into the flour mixture with a pastry cutter or with your fingers, until achieving a pea-sized crumbled mixture.
• In a measuring cup, combine the cold water and the vinegar. Pour the liquids over the crumbled flour mixture and fold everything together until just combined.
• Assemble the dough with your hands and divide it. One part would be ⅓ of the dough, and the other, ⅔ of the dough. Wrap the 2 parts in plastic wrap and cool in the refrigerator.

Make the Meat Filling

• In a large skillet on medium-high heat, drizzle the olive oil.
• Add the diced onion and minced garlic to the skillet and cook for a couple minutes before adding the pork and beef.
• Break down the meat and add the spices and salt. Add in the potato cooking water and continue cooking the meat until fully cooked.
• When the water has almost been cooked out, turn the heat off and add in the prepared mashed potatoes. Stir them in to create a unified mixture.
• Transfer the meat and potato mixture to a pan. Wrap tightly in plastic wrap and refrigerate it to cool the mixture completely.

Assemble and Bake

• Preheat the oven to 400F.
• On a floured surface, roll out the larges piece of dough. The disk of dough should be large enough to go up the sides of your pie plate and slightly overhang.
• Once the bottom pie crust is placed in plate, fill the pie with all of the meat mixture, making sure that the top is flattened.
• Roll out the smaller piece of dough to form the top of the pie. After doing so, cut out 1-3 small vent holes in the center of the disk of dough.
• Make the egg wash by mixing the egg and water together with a fork.
• Use a pastry brush to brush some egg wash on the edge of the bottom part of the pie dough. Place the top dish of dough on top, making sure that the vent holes are centered.
• Press the edges down to seal the top and bottom crusts. Holding a sharp knife vertically, run it all along the edge of the pie to trim off the excess dough.
• Use your thumb and index in one hand, with the index of the other hand, with the dough edge in the middle, to create a fluted edge. Repeat this step all around the pie to create a beautiful border.
• Brush some egg wash over the top part of the pie and the edges of the dough. Bake the freshly made meat pie in the preheated oven for 30-35 minutes, or until the crust is golden and cooked through.