Prawn and Bean Salad with Preserved Lemon Dressing

Ingredients

• 175 gm green beans, trimmed
• 600 gm canned cannellini beans, drained and rinsed
• 2 tbsp olive oil
• 12 uncooked prawns, peeled, deveined, heads removed and tails intact
• 1 tsp coarsely crushed coriander seeds
• ½ Spanish onion, thinly sliced
• 1 cup coarsely chopped flat-leaf parsley
• ½ bunch chives, cut into batons
• Preserved lemon dressing
• 200 ml extra-virgin olive oil
• Juice of 2 lemons
• ½ preserved lemon, flesh discarded, rinsed and finely chopped