Add the tomatoes and garlic and cook for another 20 minutes. Deglaze the pan with sherry vinegar and stir in the remaining ingredients; cook for 10 more minutes.
Boil the potatoes in salted water until tender, about 8 minutes. Drain and set aside. Over medium heat, sauté the chopped chorizo. Stir and cook until lightly colored and fat is rendered. Remove chorizo with a slotted spon and set aside. Add the potatoes to the pan and stir to coat with the fat. Add the sofrito and return the chorizo to the pan. Cook, stirring until everything is well combined. Remove from the heat and cool to room temperature.
Lightly coat a baking sheet with spray oil. Working with one circle at a time, brush egg wash around the outer edge. Place a rounded tablespoon of the filling mixture in the center of the pastry circle. Fold the pastry into a half-moon shape and press the edges together with your fingers. Press the edges with a fork to seal completely. Place the finished empanadas on the oiled baking sheet. Continue making empanadas with the remaining dough and filling. At this point the empanadas can be covered with plastic wrap and refrigerated for several hours.