Just like the beef and broccoli you get at a restaurant.
Set instant pot to sauté mode. While waiting for it to heat, slice flank steak into thin strips against the grain. In a small bowl, combine soy sauce, garlic, ginger, and hoisin sauce. Set aside.
When display reads "Hot" add olive oil and flank steak to the Instant Pot. Sauté for 1 to 2 minutes. Turn off pot.
Add water to pot and use wooden spatula to scrape stuck pieces from the bottom of the pot.
Pour sauce into pot over the beef. Secure the lid and make sure valve is turned to sealing.
Cook on high pressure for 10 minutes. While beef is cooking, steam broccoli in microwave. Combine cornstarch with 2 tablespoons water in small bowl.
When the Instant Pot beeps, turn valve to venting to quick release the pressure. After pressure has fully released, remove lid and turn on Sauté mode.
Add cornstarch mixture to pot. Stir often and cook until sauce thickens. Add broccoli to pot and stir to combine.
Serve over rice. Top with sesame seeds if desired.