I think I would just top and tail these first ones (snip off the coarse ends) then pop them into boiling water until cooked (or steam them) - should only take about 10 mins maximum. Either serve them up as a side vegetable or allow to cool and use in a salad. You could add them to any stew or casserole dish but it would be a shame to overcook them or overwhelm their delicate new flavour. Once they get a bit bigger, you could slice them up or use them in casseroles etc. If you google green bean recipes, there are hundreds available on line :)