Mix together the seasonings and sprinkle on all sides of the ribs.
Turn on the saute mode on the Instant Pot. Add some cooking oil to the pot and let it get hot.
Once hot, add the ribs, meat side down and sear for about 3 minutes on each side.
Turn off saute mode. Transfer the ribs to a plate.
Pour the beef stock into the pot and deglaze to remove any browned bits.
Return the meat to the pot. Top with carrots, onion, garlic and thyme.
Close the lid and set the vent to sealing. Set to pressure cook on high for 60 minutes.
When the time is up, allow for a natural pressure release, which takes about 10-15 minutes.
If desired, serve the ribs on a bed of mashed potatoes with vegetables on the side.
Notes
Short ribs take about 60 minutes in the pressure cooker to become tender. If they are larger, they might need more time. If your ribs aren't tender when cook time is up, cook for an additional 10 minutes.