Add olive oil to an instant pot and set to ‘sauté’. Season beef with salt and pepper. Once the oil is shimmering, add the beef and brown on all sides, cooking for 10 minutes total.

Remove beef with a slotted spoon and set aside. To the same pot, add onion, potato, celery and thyme and cook for 5 minutes, or until the vegetables start to soften. Season with salt and pepper.

Add tomato paste and cook for 1 minute, or until it starts to caramelize on the bottom of the pot. Deglaze with the vegetable broth and cook for 2 minutes.

Add diced tomatoes, vegetable broth and reserved beef to the pot and bring to a simmer. Once it reaches a simmer, hit cancel, then add the Instant Pot lid with the vent set to ‘sealing’.

Set to cook at high pressure for 25 minutes. When the cooking time is up, let the pressure release naturally for 15 minutes, then manual release any remaining pressure. Remove the lid.

Set the instant pot back to “sauté”. Add the frozen vegetables and let cook for 5 minutes, or until heated through. Season to taste and serve.