Add the olive oil to the Instant Pot® inner cooking pot and select the “Sauté’ function. Use the “Adjust” button to select the “More” (high) setting.
Once hot, add the roast and season with salt and black pepper, to taste. Sear the roast on all sides, approximately 3-4 minutes per side. Remove roast from Instant Pot® and transfer to a platter. Set aside.
Deglaze Instant Pot® inner pot by adding the beef broth and gently scraping the bottom with a rubber spatula to release the brown bits. Add the tomato paste, Italian seasoning, cocoa powder, and garlic powder, and stir to combine. Push the “Keep Warm/Cancel” button to turn off the Sauté function.
Return the roast to the Instant Pot® and add the lid. Lock the lid into place and set the vent to “Sealing.” Select the “Manual” button and adjust to the “High” setting, if necessary. Set cook time to 60 minutes.
When cook time is complete, allow the pressure to release naturally for 10 minutes before doing a quick release on any remaining pressure. Add onion, carrots, potatoes, and green beans on top of the roast.
Cover and lock the lid into place. Set the vent to “Sealing” and push the “Manual” button (should still be on “High.”) Adjust cook time to 3 minutes.
When cook time is complete, allow the pressure to release naturally for 5 minutes before doing a quick release on any remaining pressure.
Carefully remove lid and transfer roast and vegetables to a serving platter. Serve immediately garnished with fresh parsley leaves, if desired. Enjoy!