I grew up in a town next to a big military base, and lots of soldiers came back with Korean wives, and they brought their Korean families, so this is one of the big ethnicities to the melting pot that was the town. Anyway, this is one of the staple foods served in an oriental restaurant in town.
2 lbs beef, any cut, sliced paper thin (can sub pork or chicken)
2 c sugar
Mix beef and sugar in sealable bag and let marinate in fridge for 2 hrs up to over night.
Then, slice thinly one small onion and one small bell pepper, season w/salt and pepper, and saute in oil (about 2 tbs). Once translucent, add in the meat, and cook till well done. Serve over steamed rice.
This is a great wok dish, but works well in large skillet, too.