Turn the Instant Pot to the 'Sauté' setting and heat the olive oil.

Add the beef tips to the pot and brown them for about 5 minutes, stirring occasionally.

Add the diced onion and minced garlic to the pot, sautéing until the onions are translucent.

Pour in the beef broth and Worcestershire sauce, and season with salt and pepper. Stir to combine all ingredients.

Secure the lid of the Instant Pot and set the valve to 'Sealing'. Select the 'Manual' or 'Pressure Cook' setting and set the timer for 25 minutes on high pressure.

Once the cooking time has ended, allow the pressure to release naturally for 10 minutes, then carefully do a quick release for any remaining pressure.

In a small bowl, mix the cornstarch with 1/4 cup of water to create a slurry. Set the Instant Pot to 'Sauté' and stir in the slurry. Cook for an additional 2-3 minutes, or until the sauce thickens to your desired consistency.

Serve the beef tips hot over mashed potatoes or rice.