Turn the Instant Pot to Saute. Add the oil and heat for 1 to 2 minutes. Add the beef and the onions and saute for 2-3 minutes, just to slightly brown the beef and soften the onions.
Turn the Instant Pot off. Add in the beef stock and scape up any browned bits on the bottom of the inner pot.
To the inner pot, add in the soy sauce, garlic, ginger, red pepper flakes, and brown sugar.
Place the lid on the instant pot and be sure the vent knob is closed. Set to cook for 10 minutes on high pressure.
Once the cook time has elapsed, let pressure release naturally for 10 minutes. During that time, steam the broccoli by placing the florets into a heat safe bowl with ¼ cup of water and microwave for 3 minutes.
Once pressure has been released, remove the lid from the inner pot. Turn the Instant Pot back to Saute and let the liquid bubble. Whisk together the cornstarch with 3 tablespoons of water. Add cornstarch mixture to inner pot and cook for 2-3 minutes to thicken the sauce.
Add the steamed brococli and mix into the sauce. Serve over rice and top with sesame seeds if desired.
For the beef, use either sirloin steak, chuck roast, or stir-fry beef strips.If you opt for flank steak, decrease the cooking time to 3 minutes, as flank steak does not need as long of cook time.Leftovers can be stored in the refrigerator for up to 3 days or frozen for up to 3 months. Feel free to increase/decrease the red pepper flakes and brown sugar, based on personal preference for heat and sweetness. It is essential to use freshly grated ginger root. Do not use dried ginger as the flavor is not the same.