To cook in the Instant Pot:
Pre-heat the Instant Pot or multicooker by selecting the Saute button.Add the vegetable oil to the inside pot. As soon as the oil is hot after 1 to 2 minutes, add the chicken and pork pieces to braise.
Brown the meat pieces for 3 to 5 minutes.
Press Cancel to turn off the Saute function.
Pour the rest of the ingredients into the inside pot with the meats: cider vinegar, soy sauce, and organic broth. Add the black peppercorns, garlic cloves, bay leaves. Season with salt and ground black pepper. No need to stir.
Secure the lid of the Instant Pot. Check that the cooking pressure is on High and the release valve is set to Sealing.
Select Meats/Stews at High Pressure for 45 minutes.
When the buzzer sounds to signal cooking is complete use a quick release before opening the lid. Allow the steam to release.
Open the lid carefully. Transfer the cooked chicken and pork adobo into a large bowl. Ladle the sauce over it. Set aside to cool for about 10 to 15 minutes.*At this point, you can serve the adobo as a meal with rice if you prefer. Any adobo leftovers can be transformed to sandwiches. When chicken and pork have cooled, shred the meat on a large cutting board. Set aside the shredded meats to make into sandwiches.
To assemble Chicken-Pork Adobo Sandwiches: Slice open Pan de Sal or sourdough buns. Line the bottom of the bun with a lettuce leaf and a cucumber slice. Fill the sandwich with shredded chicken and pork adobo. Seal the sandwich with a cocktail pick garnished with cherry tomatoes. Serve warm or pack in lunchboxes. To cook Chicken-Pork Adobo on the stove-top: With the same amount of ingredients, use a large stockpot to cook the chicken-pork adobo. Follow the above procedure starting with braising the meats in hot oil. Add all the ingredients for the broth. Season with salt and black pepper. Cover and cook on the stove-top, over medium-high heat for 55 to 60 minutes or till chicken and pork are cooked completely. When meat has cooled, shred the meat and fill the sandwiches.