Perhaps you've seen this vegetable at Asian grocery stores or at farmer's markets. These long bundles of green (or purple!) pods are usually gathered together with a rubber band. Usually called Chinese long beans, they also go by asparagus bean or snake bean.
Long beans are prominent in many South, East, and Southeast Asian cuisines, where they are cooked in a variety of ways. Long beans are a type of cowpea and grow on a climbing vine. The pods grow in pairs and can reach three feet in length. When picked young and tender, they are eaten raw; the longer ones are frequently cooked in stir-fries and curries. Long beans are highly nutritious and contain good things such as protein, vitamins A & C, iron, and potassium. The taste is somewhat similar to the typical green bean.
Some long bean recipes to try:
Chinese Long Beans with Cracked Black Pepper - Food & Wine
Szechuan Long Beans - RecipeZaar
Stir-Fried Pork with Long Beans - Gourmet
Long Bean Curry - Spice India
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I love long beans. I cut them into 2" pieces, throw them into a cast iron pan with just a little oil, and cook until they start to blister and get a little black. Throw in some spicy black bean sauce at the end and you've got a side dish.
the purple ones always turn green for me. Maybe when you steam them, they might keep their color?
They also go in Som Tam! I noticed you didn't include them in your Som Tam recipe that you posted a few weeks ago (and of course, it still tastes delicious without them), but I never had a batch of green papaya salad in Thailand that didn't include long beans when I lived there.
@lotusmoss, I didn't know that! Interesting.
They'll turn green no matter how you cook them. Same with purple hull peas.
I wouldn't want to cut them. The novelty of their their unique length would be lost. Maybe keep them in the same shape, season, oil and bake and serve in banana leaf plates?