Preheat oven to 400°F (200°C). Rub the salmon with olive oil and season with salt and pepper.
Place salmon skin-side down on a baking tray, and pour the lemon juice over the top. Roast for 10-12 minutes, until cooked through.
In the meantime, make the dressing by whisking together all the ingredients.
Prepare the salad by dividing the iceberg lettuce in between bowls, top with cooked couscous, red onion, tomatoes, and feta cheese.
Once salmon is cooked, remove from oven and place on top of the salad. Drizzle with the dressing and serve.