If you've ever passed up duck eggs because you didn't know what to do with them or if you'd like them, our guide to duck eggs ...

To cook the eggs en cocotte, reduce the oven temperature ... remove the thyme and bay, then crack in a duck egg and top with the remaining sauce. Bake for 3 minutes, or until the whites have ...

A Waitrose spokesman said fertilised eggs were safe to eat and "entirely ... "There may also be instances when a wild duck encounters farmed drakes, but again, this is rare," he said.