Place the flour, salt and pepper in a large bowl. Stir to combine.
Add beef to flour mixture and toss until coated. Set aside.
Press Sauté and use the Sauté or Adjust button to select the middle ("Normal") temperature. Place 1 tablespoon of the olive oil in the inner pot Wait 2 minutes for oil to warm.
Add onion, rosemary, and thyme.
Cook with lid off, stirring occasionally until the onion softens - approximately 5 minutes. Use a large spoon to remove the onion and herbs to a bowl. Set aside.
Place remaining 2 tablespoons of oil in the inner pot, wait for oil to warm. Add half of beef. Cook with lid off - turning beef occasionally until browned. Remove and set aside. Repeat with second half of beef.
Place chicken broth in inner pot and use a spatula or wood spoon to scrape the bottom of the inner pot until the brown bits are released into the chicken broth.
Add onion, browned beef, squash, tomatoes, and Worcestershire sauce. Stir to combine.
Close and lock lid. Set the valve to "Sealing". Press cancel, then press "Manual" or "Pressure Cook" and use the level button to select "High" pressure. Use - or + buttons to set time for 20 minutes.
When the cooking cycle ends, press Cancel. Allow Instant Pot to cool and release pressure naturally - about 30 min. (you'll know the pressure is released when the small silver float button drops back down into the lid)
Remove lid and taste for seasoning, add additional salt or pepper as desired.
Serve hot, garnished with parsley. Can be served plain or over rice.