How to Make It
In a medium saucepan, bring the broth and 1 teaspoon of the salt to a boil. Stir in the couscous. Cover, remove from the heat, and let stand 5 minutes. Transfer to a large bowl and let cool. Add the tomato, peas, mint, 4 tablespoons of the oil, the lemon juice, 1/2 teaspoon of the salt, and 1/4 teaspoon pepper to the couscous.
In a large nonstick frying pan, heat the remaining 1 tablespoon oil over moderately high heat. Add the shrimp, the remaining 1/4 teaspoon salt, and 1/8 teaspoon pepper. Cook turning, until just done, about 3 minutes in all. Serve the couscous salad topped with the shrimp.
Replace the shrimp with sea scallops. Cook the scallops in the same way and for about the same length of time, until they just turn opaque.