Set instant pot to sauté. Add oil and add pork chops to inner pot.

Sprinkle with salt and pepper and brown on both sides.

Add the onion and continue cooking for 1 minute.

Mix water, both mustards, honey, salt and pepper in a measuring jug.

Switch off the instant pot and pour the water mix over the pork chops.

Scrape the browned bits off the bottom, then add the rosemary.

Close the instant pot and turn the valve to "sealing". Cook on high pressure for 8 minutes.

Switch off the instant pot and do a natural pressure release for 5 minutes, then manually release any remaining pressure before opening the instant pot.

Remove pork chops from the instant pot.

Stir the cornstarch slurry into juices.

Set instant pot to "sauté" and cook, stirring, for about a minute or until sauce has thickened.

Serve over pork chops.