Combine the masarepa, water, salt and Sazon. Start off with 2 cups of water, and add more if needed. Stir together, then knead the dough until it’s nice and smooth and slightly moist. If it’s too dry, it will crack when you seal the empanadas.Place in a bowl and cover with plastic wrap.Peel the potatoes, and place them into a pot with 3 cups of water, and 1 chicken bouillon.Boil for 20 minutes, or until fork tender.Drain them and place the potatoes into a bowl.Season the potatoes with salt and sazon, then mash until most of the chunks are gone. Add the cumin and ropa vieja.Fold to combine.Take a scoop of masa and make a ball about the size of a golf ball.Place the dough ball between 2 sheets of plastic wrap.Press the dough ball down, until it’s about ¼" thick, and 3" in diameter.Place a few teaspoons of filling in the center, then cradle the disc in your hand and pinch the empanada closed.Make sure to fully seal the edges so it doesn’t open while cooking.Fry the empanadas in vegetable oil heated to 375 degrees F for 6-8 minutes, or until golden brown. Drain on a paper towel, and serve with Aji Verde.Process the cilantro, jalapeno and scallions in a food processor.Add vinegar to get the consistency you’d like.Season with salt and pepper to taste.Store for up to 1 week in the fridge.