Make the empanada dough. In a food processor, add the flour, salt and shortening and pulse a few times until the mixture looks like wet sand.
Add the water, vinegar and eggs to the flour mixture and pulse until a ball of dough forms. Remove the dough onto a lightly floured surface and knead the dough for a few minutes until it is a smooth ball. Then wrap the dough plastic wrap and refrigerate while you make the rest of the dish.
Make the empanada filling. Heat a skillet over medium heat and drizzle with olive oil. Add the diced potatoes and jalapeño and sauté until potatoes are cooked through, about 7-10 minutes (cover the pan with a lid to help speed up the cooking).
Add the cumin, sazon, salt and pepper and toss to combine for another minute. Then add the cooked brisket and fresh cilantro and mix everything together. Turn off the heat and taste for seasoning, then set aside and let the mixture to room temperature.
Make the empanada discs. Remove the dough from the refrigerator and cut the dough in half, keeping the other half covered so it doesn’t dry out.
Roll the dough out on a lightly floured surface to a ¼ of an inch in thickness. Use a 4-inch round cookie cutter (or a standard cup works too) and cut out circles in the dough.
Preheat the oven to 375 degrees Fahrenheit.
Fill the empanadas. Place the empanada disc in the palm of your hand and fill a tablespoon of the brisket filling in the center. Wet the edges of the dough with your finger and seal the empanada on all sides, gently pushing out any air bubbles. Use your index finger to gently crimp the edges (or you can use a fork) and place empanadas on parchment lined baking sheet.
Bake the empanadas. Brush each empanada with egg wash and bake at 375 degrees Fahrenheit for 22-25 minutes until golden brown.
Make the chimichurri. To a food processor, add the passion fruit puree, cilantro and parsley, garlic, jalapeño, lime juice, water, olive oil, salt and pepper and blend together until smooth. Add more or less water for your desired consistency, but enough to be pourable.
Serve empanadas with chimichurri sauce.