Fresh periwinkles, these babies cost 2.5$ and I have no idea how to cook them.  Thankfully, the internet came to the rescue - and the answer is boil them.

But first rinse, and rinse, and rinse in cold water until the water is totally clean and there's no sand in the bottom of the bowl.

I boiled mine with a few sprigs of thyme and half a lemon, I was surprised at the aroma of the periwinkles cooking.  It smelled like the ocean on a warm summer day, with a hint of thyme and lemon.

Drain them and discard the water, then get some garlic butter and a baguette ready and you've got a delicious - if not labor intensive meal.

After going through every poking device I could think of I settled on a sewing need to pry my little sea snails out of their twirly shells.  But I suspect a sharp toothpick would work as well.

I ended up taking all my periwinkles out of the shells (once I'd had my fill) so I could use them in another dish.

And later that day we feasted on a quinoa 'risotto' with mushrooms, shallots and peas, topped with tender periwinkles - and it was absolutely delicious.