• Pat the pork dry with paper towels. Season the pork with salt and pepper.
• Click the "sauté" function of the Instant Pot and heat about 1 tablespoon of oil. Sear the pork for about 3-4 minutes or until it browns evenly on all sides. You may need to do this in 2 batches not to overcrowd the pot. Transfer the seared meat to a bowl or plate and set aside. Heat the remaining oil and sear the rest of the meat. Add additional oil if needed. Remove from the pot and press "cancel" to turn off the heat.
• Next, pour the beer, orange juice and lime juice into the pressure cooker and using a wooden spoon scrape the bottom of the pot to remove any browned bits stuck to the bottom. Stir in the rest of the ingredients and return the pork and any collected juices to the instant pot.
• Close the lid and seal the pot making sure the valve is in the sealed position. Cook on HIGH pressure for 60 minutes. After the cooking time is done, allow the pressure to release naturally for 15 minutes then, release the remaining pressure and open the lid.
• With a slotted spoon, remove the pork from the pressure cooker leaving the cooking liquid in the pot. Click the "saute" function and reduce the cooking liquid for about 5 minutes then, press cancel. Taste for seasoning.
• Meanwhile, shred the pork. Return the meat to the instant pot and toss it until well coated with the cooking liquid. Press "cancel" to turn off the heat.

Crisp up the meat (Optional)

• Turn on the oven broiler. The oven rack should be at about 6 inches from the heat source.
• Transfer some of the pork to a baking sheet, spreading the meat into an even layer. Spoon about 2 - 3 tablespoons of the cooking liquid over the pork and broil until the edges of the pork begin browning, about 2-4 minutes. Remove the baking sheet from the oven and with a spatula, flip the meat over. Broil until your desired doneness (about 2-4 additional minutes or until crispy and golden brown). Remove from the oven.
• Serve the carnitas pouring a bit of additional cooking liquid over the meat if desired. Garnish with chopped cilantro (optional).