Add the meat combined with the liquid marinade to the pressure cooker and set it on manual high pressure for 10 minutes. Quickly release the pressure valve.
Carefully remove about a 1/3 cup of the hot juices and add 2 tablespoons of cornstarch. Use a fork or a whisk to make sure the cornstarch is well combined. Add the mixture back into the pressure cooker and stir. You will notice the liquid begin to thicken as it sits.
Place the pound of broccoli in the microwave on high for about 5 minutes with 1 cup of water. This will steam it to the perfect consistency. Works for both frozen and fresh broccoli.
Drain the water from the broccoli and mix it into the beef mixture in your pressure cooker. The beef and broccoli is done and ready to serve over rice!