Select the Saute function on your Instant Pot. Add the olive oil to the pot.
Place half of the short ribs in a single layer in the pot and season with salt and pepper. Cook for 4-5 minutes per side or until golden brown. Repeat the process with the remaining meat.
Remove the meat from the pot and cover with foil to keep warm.
Add the onions and carrot to the pot. Season the vegetables with salt and pepper to taste. Cook for 5-6 minutes or until just tender and starting to brown.
Add the garlic and cook for one more minute, stirring constantly.
Add the red wine and simmer until the liquid is reduced by half, about 3-4 minutes.
Add the short ribs, thyme, bay leaf, and beef broth to the pot. Close the lid of the Instant Pot and set the valve to sealing.
Cook on high pressure for 40 minutes, then let the pressure release naturally.
Carefully unseal the pot. Take the ribs out of the pot and cover to keep warm. Discard the bay leaf and thyme sprigs. Skim any fat off the surface of the liquid.
Turn the pot back to Saute mode. Mix the cornstarch with 3 tablespoons of cold water and add it to the pot. Bring to a boil and cook for one minute or until thickened.
Add the ribs back to the pot and spoon the sauce over the top. Add salt and pepper to taste if desired. Garnish with thyme sprigs, then serve.