Step 1Combine miso paste, mirin and 1 tablespoon of soy sauce in a shallow dish. Add prawns; stir to coat. Cover the dish, and refrigerate for 1 hour.
Step 2Drain the prawns of excess marinade. Heat a chargrill pan or a barbecue hotplate over medium-high heat. Spray prawns lightly with olive oil and cook for 1–2 minutes each side, or until golden and cooked through.
Step 3Meanwhile, place asparagus, sugar snaps and broccolini in a steamer over a saucepan of simmering water. Cover; steam for 3–4 minutes, or until just tender, adding bok choy for last minute of cooking time. Drain.
Step 4Heat sesame oil in a small saucepan over a medium heat. Sauté garlic for 1 minute. Add remaining soy sauce and cook for 30 seconds, or until hot.
Step 5To serve, divide the steamed rice, grilled prawns and greens among serving plates. Drizzle the hot sesame dressing over the greens, and sprinkle meal with toasted sesame seeds.