No, it's not something from Dr Seuss, but an edible plant that grows in the salt marshes of Northern France and no doubt on the other side of the channel. The name, in French, oreilles de cochon, refers to the texture of the plant, soft leaves and crunchy stems that mimics the texture of cooked pig's ears. You can eat it it raw or cook it like spinach. As I only bought a small bunch I decided to add it to a salad.
It was very sandy, so after a good rinse in several sinks of cold water I cut it into a chiffonade and mixed it in with some red oak leaf lettuce. I expected it to be salty like salicornia (marsh samphire), but it was just pleasantly crunchy, with no strong flavour.
I found myself thinking about foods that are completely different but have the same name. In French there is a l'araignée, (spider crab) and a piece of meat (click on 14), which is not very photogenic but prized by butchers and delicious. There is another cut in the same part of the animal, la poire, which is also the the name of a fruit. How many food words are there doing double duty? Can you think of any others, in any language?