Season prepared couscous with one teaspoon lemon juice, one tablespoon olive oil, salt, and pepper, and set aside.

In a separate bowl, combine avocado, red pepper, and onion together with one tablespoon lemon juice, remaining two tablespoons olive oil, and salt and pepper.

To create a tower, divide couscous, vegetables, and lox into four equal portions. Place a ring two and a half inches (six centimeters) in diameter and two and a half inches (six centimeters) tall ring on a plate.

Press couscous into bottom of ring. Arrange a layer of vegetables on top, followed by lox.

Release ring and garnish with scallions, parsley, and sprouts.