Place trivet inside the inner pot of the pressure cooker. Pour 1 cup of cold tap water into the inner pot for a 6-quart model and 1-½ cups of water for an 8-quart Instant Pot.

Prepare glaze by whisking together pineapple juice, honey, and brown sugar in a small bowl or glass measuring cup.

Unwrap the ham, discard any plastic caps, and place the ham on large sheet of heavy duty aluminum foil. Fold up sides of foil, to make a bowl like shape around the ham. Gently separate slices of ham if sliced and pour the prepared glaze over ham.

Securely wrap foil around the ham and place ham on trivet inside pressure cooker. Secure the lid on Instant Pot and be sure the venting knob is pointed towards sealed.

Use the manual or pressure cook button to set the cooking time, using the following guidelines.For Spiral Sliced Ham: Cook for 2 minutes per pound on high pressure + time to account for the foil. If using heavy-duty foil, add 10 minutes to the total time; for regular foil, add 5 minutes to to the total cook time. For Unsliced Ham: Cook for 3 minutes per pound on high pressure + time to account for the foil. If using heavy-duty foil, add 10 minutes to the total time; for regular foil, add 5 minutes to to the total cook time.

Once the cooking time has elapsed, allow the pressure to release fully on its own. This is about 10-15 minutes.

Once pressure has been released, check the internal temperature to be sure the ham is warmed to at least 145℉. If not, cook for an additional 3-5 minutes on high pressure.

Remove the ham from the Instant Pot, remove the foil, reserving the cooking liquid that has accumulated in the foil. Let the ham rest on a cutting board for 10 minutes prior to slicing.

After 10 minutes, slice and serve with the accumulated liquid or reduction (instructions follow).

Remove trivet from inside pressure cooker and pour out the water used to cook the honey baked ham. Place the inner pot back inside the pressure cooker, add the accumulated cooking liquid reserved from the foil, hit the sauté function, and let come to bubble.

Mix together 1 tablespoon cornstarch and 2 tablespoons water in a small bowl and then whisk into liquid inside inner pot. Whisk the liquid constantly until thickened and reduced, about 3-5 minutes. Pour over sliced ham.