Pat fish dry with paper towels and remove any remaining scales or bones. Season fish fillets with salt. Heat a drizzle of oil in a medium fry-pan in high heat. Cook fish for 1–2 minutes each side, or until just cooked through. Remove from pan and set aside.
TO SERVE, Place lemon couscous on a plate, with fish on the side. Re-stir saffron yogurt and dollop on top of fish.