Sometimes the simplest recipes are best, especially if they let fresh picked vegetables shine. If you have impeccable beans, crisp and succulent, then this recipe will be perfect. Make sure to use a good-quality nut oil, because it's the main flavor component of this dish. If you like, add a sprinkle of chopped nuts to contribute texture and to support the oil's subtle taste.
Bring a large pot of water to a boil and add the salt. Add the beans and cook over high heat until they are crisp-tender, 4 to 6 minutes.
Drain immediately and transfer the beans to a large bowl.
Toss the beans with the nut oil to coat all surfaces. Add the tarragon, salt, and pepper, and toss again. Transfer the beans to a platter and garnish with the nuts, if using.