Homemade Lamb Demi-Glace (Using a Head)

Homemade lamb demi-glace is a heavily reduced meat stock, is abuilding block of classic French cuisine, requiring many hours of simmering. While it’s difficult to recreate the glace a restaurant would make, you can make an approximation at home with a lamb head and a crock pot that comes pretty close.

Lamb demi glace in a pot.
A small pot of lamb demi glace.

Pork, beef, chicken, goat, lamb and venison bones can all be used to make glace, and are interchangeable for cooking purposes.

Cooking a lamb head in a pot to make demi glace.
There’s a lot of bone and cartilage on lamb and goat heads-just what you want for demi-glace.

Traditionalists might say you need veal knuckle or other specific bones, but I can tell you after years of making glace the most important thing  is just good bones, and a long cooking time.

Cooking lamb demi glace in a crock pot.
You can make an approximation of demi-glace at home using a large crock pot and a lamb head.

How to make lamb demi glace

Technically, demi-glace is stock reduced to half of its volume. For the richest product, you want true glace, which is a further reduction arriving at around 20-30% of the starting volume of stock, or less depending on the bones you start with and the collagen they contain. The home recipe here is only reduced to 30%, but I hardly ever measure it. The most important part is that the reduction has achieved a rich, dark color and silky body. See below for how far I reduced the lamb glace I made at home.

A pot of lamb demi glace showing how far the liquid should be reduced.
Note how far I reduced this lamb head glace.

Tips

  • The easiest way to make this is in a crock pot, but for larger batches, I use a stock pot.
  • A crock pot will gradually evaporate liquid, so there usually isn’t a need for reducing the glace further after 48 hours of cooking, but the exact amount of liquid left after cooking can vary.
  • Glace is precious and will eventually go bad in the fridge, so I like to freeze it. For easy portioning, I pour the finished sauce into ice cube trays and freeze in a re-sealable vacuum bag.
An ice cube tray filled with demi glace for portioning.
Glace is easily frozen and portioned.

How to use Demi Glace

Think of glace as a meat essence you can add to sauces. Traditionally a spoonful is added to things like peppercorn sauce. Adding pureed, roasted, peeled, seeded tomatoes is a favorite of mine, and ends up tasting a bit like meaty tomato gravy. It can also be added to soups for a little color and extra flavor like you would a bouillon cube.

Black pepper and rosemary crusted lamb loin with morel mushrooms, squash and shaved brussels sprouts
Demi-glace is used to make sauces, like these morel mushrooms cooked with tomato demi-glace.

Using glace to make sauces

In professional kitchens, demi-glace is used as a building block to make lots of different sauces. Here’s some of my favorites.

Fruit glace

Adding fresh or dried fruit like blueberries with red wine vinegar and a touch of sugar, reducing down and whisking in a little butter to finish is a great, sweet-sour sauce for roasted and grilled meats.

Mushroom glace

Sweat some mushrooms in oil with a little shallot until they mushrooms have evaporated their liquid. Add a splash of red wine and reduce it by half. Add some glace-just enough to keep everything juicy, and whisk in a little unsalted butter, swirling and stirring the pan to thicken it. At restaurants, I would often make this with mushroom duxelles.

Mustard glace

Add some whole-grain mustard and a splash of heavy cream to your glace, whisking in a nob or two of unsalted butter and simmering to thicken the sauce.

Chef Alan Bergo
Chef Alan Bergo, The Forager Chef

This recipe is by Chef Alan Bergo, the Forager Chef. A chef from Minnesota and author of The Forager Chef’s Book of Flora. Learn more about Chef Alan and his hunt for mushrooms, wild and obscure foods at foragerchef.com. 

 

Lamb head demi glace in a pot.

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Lamb head demi glace
Print Recipe
5 from 1 vote

Homemade Lamb Demi-Glace (Using a Head)

Demi glace made at home using a crock pot and a lamb or goat head. Makes about 2 cups.
Prep Time15 minutes
Cook Time2 days
Total Time2 days 15 minutes
Course: Condiment
Cuisine: French
Keyword: demi glace recipe
Calories: 50kcal

Equipment

  • 1 Large stock pot of slow cooker
  • 1 Fine strainer

Ingredients

  • 3.5 lbs bones or a lamb head and a few handfuls of trim or meaty bones
  • 2 tablespoons tomato paste
  • 1 cup red wine
  • 1 small onion roughly chopped
  • 1 medium carrot roughly chopped
  • 1 rib celery roughly chopped
  • A few sprigs of fresh thyme 10 peppercorns, and 1 dried bay leaf, wrapped in cheesecloth and tied for easy removal.
  • Water as needed, about 5 cups

Instructions

  • Roast the head at 350 F for 45 minutes or until browned, then put into an 8 qt slow cooker with the remaining ingredients. Cook on low for 48 hours, then strain.
  • Chill the glace, skimming any fat that rises to the surface and discarding. Inspect the glace and it's set-it should be very firm like jello. If it isn't firmly set, you can reduce it in a small pan to concentrate it, just keep an eye on it.
  • After the glace is done, it can be refrigerated for up to a week. I like to freeze it in ice cub trays, vacuum-sealed and kept in the freezer to use as needed.

Notes

Using a head is the most efficient way to make this. Make sure to have your butcher cut the head in half for you if possible. 

Nutrition

Serving: 1tablespoon | Calories: 50kcal | Carbohydrates: 12g | Protein: 2g | Fat: 0.1g | Saturated Fat: 0.03g | Polyunsaturated Fat: 0.1g | Monounsaturated Fat: 0.02g | Sodium: 25mg | Potassium: 80mg | Fiber: 1g | Sugar: 5g | Vitamin A: 100IU | Vitamin C: 7mg | Calcium: 31mg | Iron: 2mg