Step 1 Spray a grill pan with cooking oil and set over medium–high heat. Cook pumpkin and onion, turning, for 6–8 minutes, or until golden and tender. Transfer grilled vegies to a large bowl.
Step 2 Sprinkle both sides of steak with Cajun seasoning and cook, turning once, for 3–4 minutes per side, or until done to your liking. Transfer to a plate, cover with foil to keep warm and set aside.
Step 3 Place couscous in a large heatproof bowl. Add 1½ cups boiling water, cover and set aside for 5 minutes, or until couscous has absorbed water. Use a fork to separate and fluff couscous grains; add half of the coriander leaves.
Step 4 Meanwhile, bring a medium saucepan of water to the boil. Add beans; cook for 1 minute, or until just tender. Refresh beans in cold water, then drain well.
Step 5 Cut steak into thin slices. Divide couscous among plates; top with steak, grilled vegies and beans.
Step 6 Drizzle salad with balsamic dressing, garnish with remaining coriander and serve.