Here’s how to make classic French glace de viande at home. Glace de viande is what most people erroneously call “demi glace,” and it is a thick, concentrated stock extremely useful for sauces.

Contrary to popular belief, demi-glace and glace de viande are not simply different concentrations of cooked-down stock. In classical French cuisine, demi-glace actually relies on a roux-thickened brown sauce.

I’ve literally never seen this used in more than 30 years in and out of kitchens, so at some point this definition got lost, and now most people say demi glace when they mean glace de viande.

The best way to think about what glace de viande is is as a savory meat broth Jell-O when cold, syrup when hot.

Glace, pronounced “glah-ss,” is absolutely vital for traditional pan sauces. Virtually all of them either require it, or are better when you have it. A few examples:

• Cumberland sauce
• Steak Diane
• Steak au Poivre
• Belgian venison with juniper

What’s more, a couple tablespoons of glace in whatever pan sauce you feel like making boosts flavor without running the risk of oversalting your sauce — which is a real danger when you are boiling down regular stock.

And, as you can see, there’s more than a little gelatin in glace de viande. This gelatin makes the resulting sauce silky, and gives it a richer mouthfeel you can’t get with regular stock.

Glace de Viande vs Stock

In theory, any meat or fish stock can be made into glace de viande. But in practice, most regular stocks lack enough collagen to cook down into gelatin, so no matter how much you cook the stock down, it won’t gel in the fridge, let alone at room temperature.

How to get that gelatin? Here are a few ways:

• If you are butchering the animal you’re making stock from, save all the silverskin you trim. Toss this into the pot. It is a great source of gelatin.
• Use knucklebones and other joints from the animals, especially young animals. Cartilage is the best source of gelatin.
• Buy chicken feet or pig’s feet or calves’ feet. All are excellent sources of gelatin.
• Use store-bought gelatin sheets or powder. This is technically cheating, but I won’t tell…

The only other significant difference between glace de viande and regular stock is salt. You never salt a stock you’re making into glace until the very end because often it winds up salty enough on its own.

Pro Tips

I’ve made a lot of glace over the years, and I have a few pointers and tips that will help you out when you want to make it.

First, don’t start with store-bought stock. It doesn’t work well because even the low sodium ones are still too salty. If you can find a no-salt stock, that will work.

The best glace de viande uses young animals, and a combination of raw and roasted. Roast all the meat bits, and bones that don’t have cartilage. Don’t roast feet, silverskin or cartilaginous bits. Roasting damages collagen’s ability to become gelatin in the stock.

Glace de Viande Needs Time

It’s a long process, but not a hard one. I start making the stock in the afternoon, roasting and simmering meat and cartilage, feet, etc. I let this steep — like tea — overnight on very low heat; I cover the pot.

The next morning I add vegetables and herbs, turn the heat back to an active simmer, and let this cook 2 hours. Strain through paper towels or cheesecloth to remove all particulates.

Clean the pot and return the stock to it. Turn the heat to the steaming phase, maybe a tiny shimmy. Not a full simmer. Let this cook down by at least half, and you really want to cook it down by two-thirds or more. You will need to skim the scum that forms on top.

Finally, taste it. It should taste rich, coating your mouth, and salty enough. Sometimes you need to add salt, but not usually. It should start to appear thicker than water.

Strain one more time, and you’re good.

Storing Your Glace

Once made, glace de viande will keep a week or two in your fridge. It freezes very well, and this is how I save mine. You can pressure can it, but sometimes the fierce heat and pressure seems to denature the gelatin and break it down.