In a large skillet, heat olive oil over medium-high heat.
Add beef cubes and brown on all sides, about 5-7 minutes. Transfer browned beef to a large freezer-safe bag or container.
Add diced onion, minced garlic, sliced carrots, potatoes, and celery to the bag with the beef.
In a small bowl, whisk together beef broth, tomato paste, Worcestershire sauce, dried thyme, dried rosemary, salt, and black pepper.
Pour the broth mixture into the freezer bag with the beef and vegetables.
Add bay leaves to the bag, seal tightly, and remove as much air as possible. Label and freeze until ready to cook.
When ready to cook, thaw the freezer bag overnight in the refrigerator.
Transfer the contents of the bag to the Instant Pot.
Close the lid and set the valve to sealing position.
Select the ‘Pressure Cook’ or ‘Manual’ setting and set the timer for 35 minutes on high pressure.
When cooking is complete, allow the pressure to release naturally for 10 minutes, then carefully quick release any remaining pressure.
Open the lid and remove bay leaves.
In a small bowl, mix cornstarch and cold water to create a slurry.
Set the Instant Pot to ‘Sauté’ mode and stir in the cornstarch slurry.
Cook for 3-5 minutes, stirring frequently, until the stew thickens.
Stir in frozen peas and cook for an additional 2 minutes.
Adjust seasoning with salt and black pepper as needed.
Serve hot.