1 teaspoon grated orange zest plus 2 tablespoons juice
2 tablespoons extra-virgin olive oil
1 tablespoon white-wine vinegar
Salt and pepper
1/2 pound halved red seedless grapes
3 thinly sliced stalks celery plus 1/2 cup celery leaves
Cook couscous according to package instructions. Whisk together orange zest plus juice, olive oil, and vinegar. Season with salt and pepper. Toss with couscous, grapes, and celery stalks and leaves; season with salt and pepper.