Burnt Onion Concentrate
This recipe was adapted from a Victorian-era blend that can act as either a sauce or a marinade. It’s also great for flavoring gravies, soups, and stews.
INGREDIENTS | MAKES 8 PINTS
- 3 pounds onions, peeled and coarsely chopped
- 7 ½ cups cold water
- 3 cups brown sugar
- 7 ½ cups cider vinegar
- 3 tablespoons dried French tarragon
- 1 teaspoon salt
- 1 teaspoon coarsely ground black pepper
In a large stockpot, combine onions and water. Cover; bring to a boil. Lower heat; simmer until onion is soft. Add sugar; stir well.
Continue to simmer until mixture has turned a very dark brown and has reduced by about half. This will take at least 1 hour. Stir occasionally to prevent sticking.
In a separate pan, bring vinegar, French tarragon, salt, and pepper to a boil. Lower heat; simmer 10 minutes.
Slowly pour vinegar mixture into onion mixture; stir well. Bring to a boil; lower heat, and simmer 10 minutes.
Ladle into sterilized pint jars, leaving 1" headspace. Wipe rims. Cap and seal. Process in a water-bath canner 10 minutes.

