Set the Instant Pot to Saute mode then add the oil.
When the oil is hot, add half the meat in a single layer and allow it to brown, turning only once, for about 5 minutes. Transfer to a large bowl and brown remaining stew meat. Transfer to the same bowl.
Add the onions and allow to brown on Saute mode for about 5 minutes, stirring only occasionally. Add minced garlic and tomato paste, stir, and allow to cook for an additional minute.
Add browned meat and any juices from bowl along with Worcestershire sauce, salt, thyme and beef broth. Cover and lock lid. Set to high pressure for 10 minutes.
Quick release pressure, then add the potatoes, carrots and peas. Lock lid, and cook on high pressure for another 10 minutes.
When the stew is done, quick release the pressure.
Add a couple of tablespoons of hot broth to a cup and mix with corn starch to make a slurry. Once all the corn starch has dissolved, stir the slurry into the stew. The broth should thicken a bit. For extra thick stew, use a potato masher to mash up some of the vegetables.
Add additional salt and some pepper, to taste. Serve with a nice green salad and some hot crusty bread.