Season the beef with pepper and cut it into thin strips. (Cut against the grain for tender meat)
Add the olive oil to the Instant Pot and turn to saute. Once the oil has become hot, add the beef and brown. This should take up to 10 minutes.
Pour the beef broth into the pot after the beef strips have cooked. Scrape the cooked bits off the bottom of the pot to get that flavor into the recipe!
In a medium sized bowl, stir together the soy sauce, oyster sauce, brown sugar, sesame oil, ginger, red pepper flakes, and garlic and add to the Instant Pot. Then turn off the saute function.
Seal the Instant Pot and cook for 10 minutes on high pressure. Once done, use the quick release.
Make a homemade cornstarch slurry by mixing the water and cornstarch in a bowl. Add it to the Instant Pot, turn on the saute function, and bring the slurry mixture to a boil.
Add the chopped broccoli into the pot and stir, then put on the lid and let it boil for 3 minutes. Turn off the saute function and let the mixture rest for 5 minutes.
Serve topped with sesame seeds and green onions, and enjoy!