Season 2 ½ pounds beef chuck pieces with 1 ½ teaspoons kosher salt and ½ teaspoon black pepper.
Heat 1 tablespoon of the vegetable oil in an Instant Pot or electric pressure cooker on the Sauté setting until shimmering.
Add half of the beef and sear undisturbed until browned on the bottom, 7 to 10 minutes. Transfer with tongs to a large plate.
Repeat with the remaining 1 tablespoon oil and beef. Place all the beef on the plate.
Add 1 diced medium yellow onion and 2 minced garlic cloves to the cooker and season with kosher salt and black pepper.
Cook, stirring occasionally, until softened, 3 to 4 minutes.
Add 1 tablespoon tomato paste and 1 teaspoon dried thyme to the onions and cook until the tomato paste is darkened in color, about 1 minute.
Add ½ cup beef broth and 2 tablespoons Worcestershire sauce and stir to combine, scraping up any browned bits.
Add 3 cut medium carrots, 3 quartered Yukon Gold potatoes, seared beef, and any accumulated juices from the beef, and stir to combine.
Lock the lid on and check that the valve is set to seal. Set to cook for 25 minutes on HIGH pressure.
It will take 7 to 10 minutes to come up to pressure.
When the cook time is up, let the pressure naturally release for 10 minutes.
Meanwhile, whisk 1 tablespoon cornstarch and 1 tablespoon water together.
Coarsely chop some fresh parsley leaves for garnish if desired.
Quick release any remaining pressure.
Carefully open the pressure cooker and turn on the Sauté function.
Stir in ¾ cup frozen peas and the cornstarch mixture and simmer, stirring occasionally, until the sauce is thickened, 1 to 2 minutes.
Taste and season with more kosher salt and black pepper as needed.
Serve garnished with chopped fresh parsley leaves if desired.
