Remove any string or netting from the pork. Unroll it and cut deep slits in the meat to ensure even marinating and cooking.
Rub the pork with the oregano, erythritol, salt, pepper, and olive oil and marinate for at least 3 hours, or overnight for best results.
Set your instant pot to saute, add the butter, onion, jalapenos and garlic. Saute until the onion starts to turn translucent.
Add the lime juice, zest, and chicken stock, followed by the marinated pork. Keeping the skin and fat to the top.
Place the lid on your instant pot and set to high pressure for 2 hours.
After 2 hours have passed, use the natural release technique before removing the lid.
Gently remove the pork, it will be very soft and tear apart easily. We recommend using a set of tongs in each hand or a sturdy spider tool to remove it.
Put the pork into a baking tray and shred the meat with the tongs or a pair of forks.
Turn the heat back to high and reduce the cooking juices to about 2 cups. Pour the reduced juices over the shredded pork.
To serve the carnitas, heat 1 tbsp olive oil in a non-stick pan over medium to high heat. Add the pork to the pan and press down gently.