Bring the stock to a boil. Cook couscous for the length of time indicated on the package. (Mine was 8 minutes, but this depends on the brand and size of the couscous). Drain the couscous into a fine mesh strainer and rinse under cold running water to cool. Transfer the cooled couscous to a large bowl.
Add the remaining salad ingredients to the bowl with the couscous (tomatoes, green onions, parsley, pomegranate arils, olives, and feta).
In a small bowl, add the lemon juice, garlic, salt, and pepper. Slowly drizzle in the olive oil while whisking until well combined. Add to salad and toss. Add salt and pepper to taste. Serve chilled or at room temperature.