Caul fat may be one of the more esoteric ingredients in the kitchen, but it is more than worth it to learn how to cook with caul if you work with wild game, or charcuterie.

Here’s a quick primer on cooking with caul fat, how to get it, and how to store it.

First off, caul fat is the lacey lining of the gut cavity of a variety of animals. All bovids have it, which includes cows, sheep, goats, musk ox, nilgai and bison, to name a few. All cervids have it, too, which includes all the deer, elk and moose and such. And last but not least, all the suiformes, the various piggy things, have caul fat, too — even the pig’s distant ancestor the javelina.

Caul fat is also called the omentum, and I’ve seen it called lace fat, too. It’s crepine in French and redaño in Spanish. It is, as you can see, a spiderweb of fat attached to an invisible membrane.

OK, I can feel some of you squinching your nose. Ew. Innard fat? Walk with me a moment. First, if you are not a hunter, you will almost always be buying pork caul fat that has already been cleaned. It is more or less odorless (although slightly porky), and flavorless. We’ll get to why you still want some in your life in a moment.

Obtaining Caul Fat

To the hunters, recovering caul fat from your animals isn’t terribly hard, but you have to know you want it when you gut the beast. Cut as normal, and you will likely see the lacey membranes around the stomach. I will often slice the caul as I am making this cut, but it’s not a big deal.

Now, you will need to gently lift the caul fat away from the innards, pulling it out as you go. You want it in large pieces, but some rips are inevitable. As you go, drop the sheets of caul into a plastic bag. Caul fat is generally attached close to the diaphragm and the tenderloins, near an animal’s spleen. You know you’re at the edges when the lacey membrane starts to have much larger patches of fat.

Simply rinse your caul fat in cold water, and, if there is still a smell, soak it in more cold water with a little citrus, vinegar or vanilla extract — just a touch, since you don’t want your fat to smell of vanilla. Let that sit in the fridge or other cool place an hour, then rinse with more cold water.

Regardless of whether you bought or collected your caul fat, you want to pat it dry and vacuum seal in portions before you freeze it. When buying caul fat, it is normally sold frozen. Thaw it in the fridge overnight, and then set it in a bowl of warm water. Use what you need, pat the fat dry again, and refreeze. It’ll be fine.

This warm water soak is especially important for any of you working with caul fat from bovids or cervids, meaning all the cow, sheep, goat, deer or elk type animals. The reason is because the fat of those animals is far harder (more saturated) than that of the various piggy things.

Cooking with Caul Fat

OK, so now you have some cool lacey caul fat. Now what?

This stuff has been so valuable to so many people for so long because of how caul fat works to preserve moisture in otherwise dry meats (and even fish), acts as a wrapper for things like meatballs and sausages, and, more recently, to stick food to other food — typically, say, ground meat or a mousse to the outside of a solid piece of meat.

When you cook it, the fat renders but the membrane holds. So once cooked, caul fat can be easily missed by a distracted diner. But it’s presence will be known by how juicy and lush the item wrapped with it will be.

Historically, the dominant use for caul fat is to wrap some sort of meatball. That’s what I mostly do with it. Two classic recipes employing this are French crepinettes, and the unfortunately named British meatballs known as “faggots.”

Other wrapped meatballs exist in places as disparate as Italy, Russia, and the Middle East (where they use lamb caul), to the Navajo here in the United States.

Caul fat is also a spectacular coating for terrines and pâté. I especially like using caul for my wild game terrine. Why? Caul is lighter and less fatty than bacon, which is the normal wrapping.

The other primary use for caul fat is as a wrapper for ultra lean meats — and as hunters, that’s us. Anything with internal marbling, e.g., beef, farmed pork, etc., does not need caul fat. Venison, bison, pronghorn, etc. all do. Rabbit is especially good with it.

Why? Because that gossamer wrapping essentially bastes the meat as it sears, and the membrane holds in moisture. So the net result is a more luscious bite.

Working with Caul Fat

Mechanically, you will need a large working area, a small, sharp knife, and a place to put your wrapped items. One of the greatest things about caul fat is its ability to stick to itself, like Saran Wrap. This is also a trait that can make working with caul maddening. Thus the large working area.

You want to lay out the sheets of fat in large areas, place whatever is going to be wrapped on them, then use the knife to cut pieces to shape. Always use a bit more than you think you need.

And always, when you are cooking, set the seam down into the pan when you are ready to cook. The sear on the seam seals the caul.

As I mentioned above, the caul from pigs is the finest, in my experience, followed by that from cows and other bovids. I once shot a nilgai, a distant cousin of the cow that runs wild in south Texas, and its caul fat was amazing.

Caul from cervids is nice, but it shares the same issue as cooking with deer fat, in that it gets hard and waxy as it cools. The answer is to sear venison hot and serve it without resting. The caul will hold the moisture, and your guests can then slice and eat at once.

Any scraps left over can be rendered, and although the membrane never goes away, it does get crispy eventually. I generally use scraps from deer caul fat as suet to feed birds.