Add the pork shoulder to the slow cooker. Using a small knife cut slits into the pork, about an inch down.
In a large bowl add the olive oil. Cut the lemon, lime and orange in half. Squeeze the juice out of the citrus into the bowl. Add the oregano, cumin, garlic, salt and pepper. Whisk until combined.
Pour the mixture over the pork roast. Using a spatula squish the garlic and sauce into the pork.
Add the onion rounds.
Cover and cook on LOW for 10 hours without opening the lid during the cooking time.
Shred the meat with 2 forks and remove the bone. I left about half of the juices with the meat to keep it moist.
Can I use a pork loin?You can make Cuban pork with a pork loin, but it will be much leaner and taste more on the healthy side. You will only need to cook for 7 hours on low.Can I use chicken?You can use chicken thighs instead of the pork shoulder if desired. You will only need to cook on low for 7 hours.Can I make this Spicy?Add two diced jalapenos to this recipe for a spicy dish. Or you can add one habanero instead.Can I freeze?This is the type of meal that freezes very well! Freeze for up to three months in small ziplock bags or airtight containers.