Step 1: Cut pork shoulder into 1/2-inch cubes. Season generously with Adobo seasoning, 1 packet Sazón, and black pepper. Marinate for at least 30 minutes, or preferably overnight, in the refrigerator.
Step 2: In a large pot or Dutch oven, heat 2 tablespoons of olive oil over medium-high heat. Brown the pork cubes in batches until nicely seared on all sides. Remove pork and set aside.
Step 3: Reduce heat to medium. Add 1/4 cup of the sofrito to the pot, cooking for 3-5 minutes until fragrant. Add tomato sauce and cook for another 5 minutes, scraping up any browned bits from the bottom of the pot.
Step 4: Return pork to the pot. Add olives, capers, bay leaf, and beef broth. Bring to a simmer, then reduce heat to low, cover, and cook for 1.5 to 2 hours, or until pork is very tender and easily shreds. Remove bay leaf. Shred the pork with two forks and set aside to cool. Reserve about 1/2 cup of the cooking liquid.
Step 5: Peel and roughly chop the green plantains, green bananas, yautía, and calabaza. Keep them submerged in acidulated water until ready to process to prevent oxidation.
Step 6: Using a food processor or a traditional ‘pilón’, work in batches to finely grate or puree the chopped vegetables until a smooth, thick batter (masa) forms.
Step 7: In a separate bowl, whisk together the remaining 1/4 cup sofrito, achiote oil, and the reserved pork cooking liquid. Season with Adobo and 1 packet Sazón. Add this mixture to the pureed masa, mixing thoroughly until evenly colored and combined. Taste and adjust seasoning.
Step 8: Prepare your banana leaves by washing thoroughly and softening them over a low flame or in hot water. Cut them into approximately 10×10 inch squares. Cut parchment paper into slightly smaller squares (about 8×8 inches).
Step 9: Lay a banana leaf square flat, then place a parchment paper square on top. Brush the center of the parchment paper with a thin layer of achiote oil.
Step 10: Place about 1/4 cup of masa mixture onto the center of the parchment paper. Create a slight well in the center. Spoon about 2-3 tablespoons of the cooled pork filling into the well.
Step 11: Carefully fold the parchment paper over the filling, bringing one side of the masa to meet the other, enclosing the filling. Then fold the banana leaf over, creating a secure packet. Fold the ends of the banana leaf packet to create a tight, rectangular package.
Step 12: Bring a large pot of salted water to a rolling boil. Carefully add the pasteles, ensuring they are fully submerged. Cook for 1 to 1.5 hours, depending on their size.
Step 13: Carefully remove pasteles from the water using tongs. Let them rest for a few minutes before unwrapping and serving hot.