Cook couscous
Bring 1 cup water to a boil, add salt and olive oil.
Add couscous, stir to combine and remove from heat. Cover and let sit for 5 minutes.
Fluff cooked couscous with a fork and let cool completely.
Make dressing
In a small bowl, combine lemon juice, vinegar, salt and pepper. Whisk to combine.
Slowly drizzle in olive oil while whisking constantly.
Set aside until ready to assemble salad.
Assemble salad
In a medium bowl, combine cucumber, tomatoes, bell pepper, olives, feta, scallions, parsley, dill, mint and lemon zest.
Add cooled couscous and toss to combine.
Whisk dressing to emulsify again and pour over salad.
Toss to combine and serve.