Prepare the couscous according to package directions, making sure to fluff it well with a fork when it's cooked.
In a small bowl, whisk together the olive oil, vinegar, lemon zest, lemon juice, and salt. Set aside.
Pour the prepared couscous into a large mixing bowl. Add the cranberries, blue cheese, scallions, and pecans and pour the dressing evenly over the top. Mix everything together lightly with a fork so the ingredients are lightly coated with the dressing and the mixture stays fluffy.
Taste the salad for seasoning, and add another pinch or two of salt if necessary.
For best results, prepare at least 2 hours in advance and chill it, covered, in the refrigerator before serving.