Mince the garlic, dice the onion and jalapeños and set aside. Trim the extra fat from the pork shoulder and cut into 8 portions. Combine the rub ingredients and massage into the pork.
Turn the instant pot on to Saute and add 1 tbsp olive oil. Once hot, sear 1/2 the meat on all sides, remove from the pot then sear the second half of the meat. Remove the second batch of seared meat then pour in ½ cup bone stock to degalze the pot by scrubbing off all of the little blackened bits with a wooden spoon.
Return the meat to the pot, pour in the rest of the stock then, without stirring, add the onion, garlic and jalapeños. Juice the limes over top of the other ingredients, then secure the instant pot lid. Turn the steam release valve to the sealed position then, using the pressure cook mode, pressure cook for 70 minutes.
Once complete, you can allow your instant pot to naturally release, or go ahead and carefully, using all the necessary precautions, quick release.