Sprinkle ribs with salt and pepper. Select saute setting on a 6-qt. electric pressure cooker and adjust for medium heat. Add oil. Working in batches, brown ribs on all sides; transfer to aplate and keep warm.
Add onions to cooker; cook and stir until tender, 8-9 minutes. Add garlic and tomatopaste; cook and stir 1 minute more. Stir in beef broth, wine, thyme and
bay leaf. Bring to a boil; cook 8-10 minutes or until liquid is reduced by half. Add ribsback to cooker, partially but not fully submerging them. Lock lid; close the
pressure-release valve. Adjust to pressure-cook on high for 40 minutes. Quick-release pressure. Add carrots; bring back to full pressure and cook 7 minutes. Quick-release pressure. Press cancel.
Remove ribs and vegetables; keep warm. Skim fat from cooking liquid. Discard thymeand bay leaf. Select saute setting and adjust for medium heat; bring cooking juices to aboil. In a small bowl, mix cornstarch and water until smooth; stir into juices. Return to aboil; cook and stir until thickened, 1-2 minutes. Serve with ribs and vegetables.