If you make a big batch, it’s easier to use a wok. A smaller frying pan will work too, but you might have to fry the meat in two batches, so the pan isn’t overcrowded.
Start cooking rice according to package instructions.
Thinly slice beef against the grain and mix in a bowl with rice wine vinegar, 2 tablespoon soy sauce, and 1 tablespoon cornstarch.
Mix the remaining soy sauce with the hoisin sauce, sambal oelek, and ginger, and set aside.
Bring a pot of water to a boil and blanch broccoli for 2 minutes.
Bring peanut oil to a simmer over high heat and add the beef. Stir fry until browned, about 2 minutes. If using a smaller pan, stir fry the beef in two batches, using half the oil each time.
Set the beef aside and clean out your pan with some paper towels.
Bring 1 tablespoon oil to nearly smoking (high heat, but no smoke) and stir fry your vegetables for 2 minutes.
Return the beef to the pan and add the sauce.
Stir everything together until nice and smooth, for less than a minute.
Add the butter, and within less then another minute, you’re done!