Slipper Shell, Poop-Deck Shell, Boat Shell: Whatever You Call It, You Can Also Call It Dinner
What washes up on Cape Cod beaches, can change gender, tastes great in spaghetti, and looks like a slipper?
“Crepidula fornicate,” the late Dave Masch, of Woods Hole, told me. “The slipper shell, or boat shell. Or some people call them poop-deck shell."
"It’s an edible gastropod eaten by very few people," he went on. "It sort of looks like a round-bottomed slipper, if you could have a round-bottomed slipper—you’d be tilting all over the place—and half of it is decked over with shell and the other end of it is open so the foot can come out. So I assume the things move around. I don’t know how the hell they do it… I mean, I’m puzzled by them.”
They are strange creatures. For starters, the species, which is a type of snail, is what’s called a sequential hermaphrodite. The animals live stacked up on top of each other, with the bottom snails clinging to things like rocks, shells, and dock pilings. These larger, older animals on the bottom of the pile are always females, while the smaller, younger snails on top are males. If the females die, the largest male will change gender, and move to the bottom of the stack.
“You see how they’re on a pile like that?” Dave said, showing them to me. “Smallest on top and down, down, down to the biggest ones? When you find them alive and turn them over, you’ll see a fleshy bit of meat at the bottom. And you can see the deck at one end of the shell. What you do is: put your thumb on the deck and just push forward, down on the meat. The meat will push right out of the shell. Then you’ll have this little glob of yellowish white, ivory-colored meat with some black stuff connected to it. The whole thing is edible. When you eat them raw, they’re very sweet—they’re very chewy, but they’re sweet and delicious.”
Masch said they have the flavor of a scallop, and their texture is somewhere between a squid and a conch. He liked to eat them in pasta, in a twist on the traditional red clam sauce. He’d steam the slipper meats out of their shells, then add them to a tomato sauce with a bit of their cooking juice for flavor. This gets served over spaghetti.
“I knew about the shells just from wandering on the beach, but I didn’t know about eating them,” Masch said. “I was talking to a guy who was a very successful fishing captain from Hyannis, and his son became a fishermen later, too. His son grew up eating them. When they were children they’d find them on the beach, and they called them swede meats. The kids would just sit around and pick away at them, and some kids would eat them. And probably some of the kids said, ‘Yuck, I wouldn’t eat that in a thousand years!’ So after hearing that, I tried them. I found them nice raw, so I decided to try to cook them—since cooking is my thing, and cooking seafood in particular. I was quite happy with them. Still am.
Slipper shells wash up on the south side of the Cape after big storms, but you can find them on the bay side and on the beaches of the islands, too. They can stay alive out of the water for at least a few days, if not longer, like many shellfish. If I can muster the courage to eat one, I’m going to try Dave’s recipe for sweet meats in red sauce.
Here’s the recipe:
SWEET MEATS IN RED SAUCE
by Dave Masch
3 cups tomato sauce, preferably homemade
1 cup slipper shell meats, chopped
2 cloves garlic, finely chopped
3 tablespoons Italian parsley, minced
2 tablespoons olive oil
red pepper flakes to taste
1 pound linguine, cooked
Heat up tomato sauce in a large, heavy-bottomed pot. Add all ingredients but the linguine. Simmer for three minutes and serve over the linguine. (Dave said he likes it quite peppery hot, but how many red pepper flakes you add is definitely a personal choice. Sometimes he adds Tabasco, too.) "That's all there is to it! Go for it, you won't be sorry," he said.
He had a few other notes. For starters, in order to extract the slipper meats from their shells, you can steam them briefly, for about 2 or 3 minutes in water, white wine, or beer. "You should be able to winkle them out in a trice!"
He also offered a recipe for a nice light tomato sauce, in case you don't have any tucked away. It is comprised simply of one 28-ounce can of whole tomatoes in puree, 2 small sliced onions, salt and pepper to taste, and a teaspoon of dried basil, "or oregano, terragon, or any other herb you fancy." You simply simmer these ingredients together for 20 minutes, stirring frequently, and if you want a smooth sauce, in the end, you puree it. And maybe, if you feel like it, you can add in 4 tablespoons of butter at the end, just for good measure (although if you do that, you might not want to tell people it's "light").