Preheat the oven to 375°F
Place the lentils, bay leaf and salt is a saucepan, cover with water and bring to a simmer. Cook for 25-30 minutes, or until the lentils are tender. Drain and discard bay leaf.
In a small saucepan, combine the quinoa with 2 cups of water and the salt. Bring to a simmer, reduce heat to low, cover and cook for 12 minutes.
Place the bulgur wheat in a heatproof bowl. Pour 1 cup of boiling water on top and let it sit until the water is absorbed and the grains are tender. Drain off any excess water.
In a large bowl, toss together the lentils, quinoa, bulger, cucumber, onion, lemon juice, olive oil, parsley, mint, garlic, salt and pepper.
In a small bowl, combine the ginger, chives, chile flakes, oil, salt and pepper.
Pat the salmon fillets dry and season with salt and pepper on a baking sheet. Divide the ginger sauce between the fillets, coating each one.
Pat the salmon dry, season with salt and pepper and arrange on a baking sheet. Cover with lemon slices and roast for 12-15 minutes, until cooked through.
In a blender, combine the garlic, lemon juice, tahini, water, and olive oil until smooth. Add the remaining harissa yogurt ingredients and process until smooth. Season to taste.
To serve, divide the tabbouleh and salmon between plates. Top with arugula and serve with harissa yogurt and a lemon wedge on the side.