In large bowl, toss beef with salt and pepper. Spray 6-quart Instant Pot™ insert with cooking spray. Select Saute; adjust to normal. Melt butter in insert. Add beef in 2 batches, and cook 2 to 4 Minutes on first side until browned. Turn and cook 2 to 4 Minutes longer on second side or until browned. Select Cancel.
Return beef to insert. Stir in tomato paste. Stir in onions, carrots and potatoes. Stir in broth. Secure lid; set pressure valve to Sealing. Select Manual; cook on high pressure 45 Minutes. Select Cancel. Set pressure valve to Venting to quick-release pressure.
In small bowl, beat cornstarch and water with whisk. Select Saute, and adjust to normal; heat liquid to simmering. Gently stir in cornstarch mixture; cook 30 to 60 Seconds, stirring frequently, until thickened. Select Cancel.