First, place pork shoulder on a large plate or cutting board.
Prepare pork dry rub by placing spices into a medium bowl. Mix until combined.
Pour spices over the pork shoulder and massage spices into the meat, making sure to be generous! This adds so much flavor. Set aside.
Turn on the Instant Pot's saute feature and add olive oil. When olive oil is fragrant, sear pork shoulder for 2-3 minutes on each side. The goal here is to get each side nicely browned. Turn the Instant Pot's saute feature off and pour green chilis over the pork shoulder. Add water, and cover Instant Pot.
Turn pressure valve to seal >> turn the Instant pot to high pressure >> and set the timer to 90 minutes. It will take up to 15 minutes for pressure to build inside the Instant Pot. Once this happens, it will start counting down from 90 minutes.
When the Instant Pot beeps, quick release pressure by turning pressure valve to vent.
Take cover off Instant Pot and then remove any large fat chunks from the pork.
Use 2 forks to shred the remaining pork. It should be fall-off-the-bone and easy to shred. If it's not, consider pressure cooking for a longer amount of time.
Once shredded, squeeze on lime juice and mix.
Serve immediately OR make them extra crispy!
To make your carnitas extra crispy, spray a baking sheet with nonstick cooking spray. Then, transfer carnitas onto baking sheet and evenly spread out. Broil on high for 3-5 minutes. Then, toss and continue broiling until the edges are nice and crispy!