Wing Beans are wonderful. They are best when small and cut accross ways are crunchy and good in salad, a little bigger and great steamed or stirfried.
I added them into this grated salad- Green pawpaw, raw pumpkin, toasted coconut shred, toasted sesame seeds, mint, lime juice, a little chili, fish sauce and palm sugar. Every fresh ingedient from the garden.
Tasteofthetopend 
What I love about wing bean plants is that it grows well here in the tropics AND you can eat the leaves, flowers, green beans, dry the seed and eat as a soup bean and lastly when your plant dies dig the tuber and eat that too.
Some of my blog readers in the UK know wing beans as asparagus pea.