Place pork shoulder on baking sheet without the marinade and loosely cover with another sheet of aluminum foil. You want it sealed but still have enough room for air to circulate.
Let the pork shoulder cool for about 30 minutes, and then pull apart, but don’t shred it. You still want big chunky pieces.
*You will have leftover pulled pork. You can make more tostones buns to serve more people or freeze it for later use.
Slow cooker method: cook on low for 10-12 hours depending on size of pork shoulder.
Instant Pot method: cut pork into large chunks, add it to the Instant Pot with about a cup of liquid from the marinade. Close the lid, seal it, and then press the "pressure cook" or "pressure" button, set the time for 90 minutes on high pressure. Once done, let the Instant Pot naturally release or wait 10 minutes before manually release. Shred the pork and crisp up in a skillet if you want!