Step 1Combine lemon juice, crushed garlic and olive oil in a large glass or ceramic dish. Score inside of calamari with a sharp knife and cut in half or 4cm pieces. Add prawns and calamari to lemon and garlic marinade; stir to coat. Cover and set aside in fridge to marinate for at least 1 hour.
Step 2Preheat oven to 180°C. Line a baking tray with baking paper. Drain chickpeas on a plate lined with paper towels for 10 minutes. Spread chickpeas on prepared tray. Spray chickpeas with olive oil and sprinkle with cumin. Roast for 15 minutes, or until golden. Remove from oven and set aside.
Step 3Meanwhile, make the Romesco dressing: Put all the ingredients in a blender and blitz until smooth. Season dressing with cracked black pepper and set aside.
Step 4Heat a grill pan or barbecue hotplate to high heat. Drain the calamari and prawns of excess lemon and garlic marinade. Grill seafood for 1–2 minutes per side, or until lightly charred and just cooked through. Set aside.
Step 5Combine baby rocket, onion, fresh herbs, roast chickpeas and seafood in a large salad bowl; gently toss to combine. Pile salad onto a serving platter; drizzle with Romesco dressing and serve with lemon wedges.