These fall-off-the-bone short ribs deliver rich, tender perfection in a fraction of the usual time. A comforting, impressive meal any night of the week.
Season the short ribs generously on all sides with salt and black pepper. Set the Instant Pot to saute mode and add the olive oil. Working in batches, sear the short ribs for about 2 to 3 minutes on each side until deeply browned. Transfer to a plate and set aside.
Add the chopped onion, carrots, and celery to the pot. Saute for 4 minutes until the vegetables begin to soften. Add the smashed garlic and tomato paste and stir for 1 minute until the paste darkens slightly.
Pour in the red wine and scrape up all the browned bits from the bottom of the pot. Let it simmer for about 2 minutes to cook off the alcohol. Pour in the beef broth and stir to combine.
Return the short ribs to the pot, nestling them into the liquid. Tuck the rosemary and thyme sprigs between the ribs. Lock the lid, set the valve to sealing, and cook on high pressure for 45 minutes.
When the cook time is done, let the pressure release naturally for 15 minutes, then carefully turn the valve to venting. Transfer the short ribs to a serving platter and tent with foil.
Discard the herb sprigs. Set the Instant Pot to saute mode. Whisk together the cornstarch and cold water, then stir it into the braising liquid. Let the sauce simmer for 3 to 4 minutes until it thickens.
Spoon the thickened sauce and braised vegetables over the short ribs and serve.