Place pork chops at the bottom of the Instant Pot.
Pour apple juice and beef broth on top of pork chops, then top with butter.
Sprinkle dry onion soup mix, all the seasonings, onions, and fresh mushrooms on top of the pork chops.
Put your lid on the pot and move the VALVE to sealing (not venting). Press the MANUAL (or PRESSURE COOK) button and set timer for 6 minutes.
The pot will come to pressure (it will take about 10-15 minutes) and then it will begin cooking.
When timer is finished, let pressure do a NATURAL RELEASE (it will take at least 20 minutes).
When the pin drops down and all of the pressure is released, remove the lid and check the pork chops with a meat thermometer to make sure that the internal temperature has reached 145 degrees.
Remove pork chops from the Instant Pot and cover, then set aside.
In a small bowl, mix together 1 1/2 Tablespoons cornstarch with 1 1/2 Tablespoons of water. Pour into the Instant Pot with the remaining liquid.
Press the SAUTE button and let the liquid come to a boil, whisking the cornstarch mixture in. Cook until liquid becomes thick enough to make a gravy.
Serve pork chops topped with onions, mushrooms, and gravy.