Scallop rillettes with lemon and vanilla

Name: Scallop rillettes with lemon and vanilla
Cuisine: European, British
Ingredients: 6 prepared scallops, with the coral cut into quarters; 100g finely chopped shallots; 100g finely chopped onions; 200g pouring cream; 100g Isigny AOP butter; 3 centilitres of Noilly Prat (or vermouth or Martini); The zest and juice of one lemon; A whole vanilla pod; Table salt, freshly ground pepper, butter for cooking.