Beef Demi-Glace Gravy

Demi-glace gets thrown around loosely on menus, but it means one specific thing: espagnole sauce and brown stock in equal measure, reduced by half and strained. It takes a day and it is the most useful thing you can have in the freezer. A tablespoon of it will rescue almost any gravy.

Ingredients

Makes about 750ml, and a little goes a long way

• 1 litre (1.75 pints) espagnole sauce see the Espagnole recipe, or make it as below
• 1 litre (1.75 pints) brown beef stock unsalted, ideally home made
• 60g (2oz) butter for the espagnole roux if making it fresh
• 60g (2oz) plain flour
• 1 small onion finely diced
• 1 small carrot finely diced
• 1 stick celery finely diced
• 1 tbsp tomato purée
• 1 bay leaf
• 2 sprigs thyme
• 20g (0.75oz) cold butter to finish
• salt

Kit

• Heavy based saucepan
• Wide sauté pan
• Fine sieve
• Ladle

Method

1. If you are making the espagnole fresh, melt the 60g of butter in a heavy pan and stir in the flour. Cook it over medium low heat for 12 to 15 minutes, stirring often, until the roux is the colour of an old penny and smells like toasted hazelnuts. This is a brown roux and it takes patience, but rushing it on high heat gives you burnt specks and no thickening power.

2. Stir the diced vegetables into the roux and cook for 5 minutes, then add the tomato purée and cook another 2 minutes. Whisk in 1 litre of the brown stock a ladle at a time, keeping it smooth, then add the bay and thyme and simmer very gently for an hour, skimming the skin that forms at the edge. Strain, and that is your espagnole.

3. Pour the espagnole and the second litre of brown stock into a wide pan. Wide matters, because reduction happens at the surface and a tall narrow pan will take twice as long.

4. Bring to a gentle simmer and hold it there. Do not boil it hard, because a hard boil forces the fat back into the sauce and it will never look glossy.

5. Reduce by half over 2 to 3 hours, which sounds vague until you mark the level with a wooden skewer at the start. Skim the fat and skin off the side of the pan every 20 minutes. Classical kitchens call this depouillage, and it is the whole reason a good demi-glace tastes clean rather than heavy.

6. You are done when the sauce coats the back of a spoon and holds a clean line when you draw a finger through it. It should be roughly the thickness of single cream while hot, because it thickens further as it cools.

7. Strain through a fine sieve into a clean pan. Taste and season with salt, then whisk in the cold butter off the heat for shine.

8. To serve as gravy, thin about 250ml of demi-glace with 100ml of hot stock or the juices from whatever you have roasted. Neat demi-glace is too intense to pour over a plate.

Tips worth knowing

• Mark your starting level on a wooden skewer or the handle of a spoon. Guessing at half is how people end up with a sauce that is either thin or gluey.
• Skim from one side. Pull the pan slightly off centre on the burner so the convection pushes all the fat and skin to the cool edge where you can lift it off in one go.
• Freeze demi-glace in an ice cube tray. One cube dropped into a pan gravy turns an average one into a proper one.
• If it sets solid in the fridge, that is correct. It should be a firm wobbly block, not a liquid.

Keeping and reheating

Keeps a week in the fridge as a set block and six months in the freezer. Reheat gently with a splash of stock, never in the microwave on full power or it will separate.

Questions people ask