Add mussels to boiling water, bring to a boil and cook for 1 minute. Remove from heat and drain.
Cut the onions into rings and fry in vegetable oil until soft.
Add mussels, salt to taste and lemon to the onion. Cover and cook for 5 minutes stirring occasionally.
Add greens to mussels to taste or at will and serve.
Mussels with lemon are very juicy, tasty and fragrant. Cooking is very simple and fast, this dish is perfect for any side dish or as an appetizer for beer. The amount of lemon can be changed to your taste. Greens will give the dish brightness and freshness, but adding is not necessary.