Couscous Salad with Plums and Smoked Duck

Name: Couscous Salad with Plums and Smoked Duck
Ingredients: One 10-ounce box instant couscous (about 1 2/3 cups); Kosher salt; 1 2/3 cups very hot tap water; 1/4 cup plus 2 tablespoons fresh lemon juice; 2 1/2 teaspoons ground cumin; 1 1/2 teaspoons minced garlic; 1 1/2 teaspoons finely grated lemon zest; 1/2 cup plus 2 tablespoons extra-virgin olive oil; Freshly ground pepper; 1 tablespoon finely chopped rosemary; 3 ripe purple or red plums, cut into 1/2-inch dice; 1/4 pound mesclun (6 cups); 1 large smoked duck breast half (14 ounces), skinned and thinly sliced crosswise