Cold Mussels Plaki

• 48 large mussels
• Salt
• 2 medium onions, chopped
• ½ teacup

Wash and scrape the mussels clean. Open them by steaming in a covered saucepan with about 300 ml (½ pint) vigorously boiling water and a little salt for 5 to 7 minutes. Remove the mussels from their shells