Pat the beans dry if necessary, cut into bite size 1" pieces. In a large bowl, combine the blanched beans, drained and rinsed canned beans, scallions, and grape tomatoes. Pour the dressing over the mixture and toss to coat. Let the salad sit for at least 15 minutes to allow the flavors to meld.
1/2 lb fresh beans, trimmed, 1 can beans of choice, drained and rinsed, 1/4 cup scallions, white and green parts, 1/4 cup grape tomatoes, halved or quartered