- 1/2 teaspoon dried thyme
- 3 to 4 fresh parsley stems
- 7 to 8 whole black peppercorns
- 1 bay leaf
- 2 cups sauce espagnole
- 2 cups beef stock
Wrap the thyme, parsley stems, peppercorns, and bay leaf in a piece of cheesecloth.
Combine the brown sauce and the beef stock in a heavy-bottomed saucepan. Bring to a boil over medium-high heat, then lower heat to a simmer. Add the cheesecloth bundle, and reduce the liquid for about 45 minutes, or until the total volume has reduced by half. Remove pan from heat and retrieve the sachet.
Carefully pour the demi-glace through a wire mesh strainer lined with a piece of cheesecloth.