Ingredients:

1 lb. long, slender green beans such as Blue Lake or Kentucky Wonder, ends trimmed 
1/2 cup chopped fresh mint  
2 Tbs. extra-virgin olive oil 
1/2 tsp. kosher salt 
1 or 2 yellow tomatoes, cut into wedges about 1/2 inch thick 
1/2 cup scallions, sliced-thin
2 tsp. white vinegar, or to taste 
Freshly ground pepper, to taste 

Directions:

Bring a large pot three-fourths full of water to a boil. Add the green beans to the boiling water and cook until tender, 5 to 7 minutes; the timing will depend on their size. Drain.
In a large serving bowl, combine the hot beans, mint, olive oil and salt and toss to mix. Set aside to cool to room temperature, about 20 minutes.
Just before serving, add the tomatoes, onion, vinegar and a grind of pepper to the bean mixture and toss to mix. Taste and add more vinegar, if necessary. Serve the salad at room temperature.

Image: William Sonoma