We picked up a bunch of string beans from an Indian grocery store since we were kinda getting fed up with the usual cabbage, carrot and beans. I depend entirely on the Internet for recipes and since i couldn't find a good enough (read simple) recipe for string beans thoran, here i am posting my own recipe with the outline from one i found online.
String beans- 1 bunch
Dry red chilli- 5 or 6 depending on your spice intake. Crush these with the back of a ladle or spoon
Mustard seeds- 1 tsp
Curry leaves- 1 sprig
salt- to taste
oil- about 3 tbs (I use as little as possible)
Heat some oil in a frying pan, add mustard seeds and curry leaves. As soon as they start to splutter, add the crushed red chillis and sautee for a minute or so. Add the string beans (diced into 1inch pieces) and sautee well. Add enough salt and if its not spicy enough, at this stage you can add some chilli powder or paprika. Cook covered till its done (about 5minutes) and make sure you do not add any water.