1 Heat olive oil in a skillet over medium heat. Add walnuts and stir until lightly toasted and fragrant, about 4 minutes.2 Add garlic and cook 1 minute. Remove from heat and let cool. Toss with mint and cilantro. 3 In a medium saucepan, bring broth or water to a boil. Add couscous. 4 Remove from heat, cover and let stand 5 minutes. Fluff with a fork and stir in walnut-herb mixture.