In gallon freezer bag, combine ginger, red pepper flakes, cornstarch, garlic cloves, soy sauce, apple cider vinegar, beef stock and flat iron steak. (I like using a plastic freezer bag holder to hold the bag open while I'm filling it.)
Work out air and seal bag closed. Let meat marinate in a refrigerator or cooler for at least 1 hour or overnight. (see Note #1)
Cook At Camp (see Note #2)
Prepare equipment for cooking over medium-high heat.
Dump all of the meat and enough liquid to cover the meat from the bag into your Dutch oven, on your Blackstone or in a skillet. Reserve the remaining liquid in the bag. Simmer covered until almost cooked through, about 10 minutes. (see Note #3)
Now, add the broccoli, toss together and finish cooking covered until broccoli is tender and meat is fully cooked through, about 10 more minutes. If you need more moisture to steam the broccoli, add liquid reserved in the bag. If you have enough liquid, dispose of the liquid in the bag.
While the beef and broccoli are simmering, cook or reheat the rice.
Serve over jasmine rice and top with green onions.
Notes
If preparing as a freezer meal, label outside of bag with name, cooking and serving instructions. Seal and lay flat in freezer.
If prepared as a freezer meal, allow enough time to defrost freezer bag prior to cooking.
There is quite a bit of liquid in the bag, it's the liquid that will steam the broccoli during the cooking process.