The first time I tried to tackle a whole skate wing, a spike near the edge of the fin jabbed right into the joint on my ring finger above the knuckle. The spike must have hit a nerve because it sent pain shivers down my forearm and left a thin, long bruise, like a streak of charcoal, running down my ring finger.
If you've only bought skate wings from a fishmonger who's filleted the flesh for you, then it may not be obvious why the fillets are called "wings" when they resemble any other fish fillet, albeit with deeper grooves in the flesh. The flesh, in fact, is meaty and lean, with a corrugated surface.
But these strange, bottom-dwelling fish—that resemble a cross between a sting ray and a fish—are really sharks with pectoral fins so large they're referred to as "wings." This is more apparent if you take home one of its two "wings" without having your fishmonger do anything (like skinning, which gets rid of the spikes protruding from the leathery, shark-like exterior, or filleting, which removes the meat from the cartilaginous bone of the animal).
As sharks, skates have no bones, but rather a skeleton of cartilage that cooks nicely in a soup preparation once the fillets are taken off.
Though it may seem a daunting task to prepare a skate wing on your own, doing so is more a matter of strength and resolve than skill.
How to Fillet the Wing
The best way to remove the skin is to take a pair of pliers and pull the skin clean off the flesh, then lay the skate with its gray (and spiky) side up. Pulling off the skin in this way takes a bit of strength, and if you lack it (or the necessary pair of pliers), the second best option is taking a sharp knife and running the edge along the underside of the skin. The other side of the wing is covered by a white, leathery piece of skin that can be removed in the same way to expose a small, thinner fillet.
How to Cook Skate
Skate wing is often paired with capers because the sourness is a nice foil to the flesh: tender, firm, and delicate without being fragile like flounder. When cooking the fillets of skate wings, the grooves of the flesh become more pronounced and tear away sliver by sliver. You can poach the fillets in wine and stock or brown them, lightly dredged in flour, in a hot pan with butter. To augment the sourness of the sauce, I like to add tomatoes to the base of capers and shallots, and mix it with olive oil for a richer flavor.
If you do end up buying a whole skate wing, chop the cartilage into sections to use for a fish soup or stew. The cartilage adds a body to the stock, and what flesh you leave clinging to the bone will be tender and flavorful.