This is a perfect salad to take to a picnic or potluck since it is best at room temperature.
Place bulgur in a small heatproof bowl; add the 1/2 cup boiling water and let sit 30 minutes. Fluff with a fork.
In a large saucepan, blanch green beans in boiling salted water until crisp-tender, 3 to 5 minutes. Drain and immediately plunge in ice water. Drain well.
In a large bowl, combine the bulgur, green beans, parsley and mint. Toss with lemon juice and olive oil; season with salt and pepper. Add tomatoes. Serve salad at room temperature.