Leftover onions keep in the refrigerator for about two weeks.
Recipe information
Yield
Makes about 8 cups
Ingredients
2 pounds red onions, thinly sliced, separated into rings
6 4-inch fresh rosemary sprigs
2 cups Champagne vinegar or white wine vinegar
1 1/2 cups water
1 cup sugar
1 heaping tablespoon mixed pickling spice
2 teaspoons coarse kosher salt
Preparation
Step 1
Place 1/3 of onions in large (at least 2-quart) jar with tight-fitting lid. Add 2 rosemary sprigs. Repeat layering twice more with remaining onions and rosemary.
Step 2
Bring vinegar, 1 1/2 cups water, sugar, pickling spice, and salt to boil in medium saucepan over high heat, stirring until sugar dissolves. Reduce heat and simmer 2 minutes, stirring often. Pour hot liquid over onions, pushing onions down into liquid. If necessary, add just enough cold water to cover onions. Cool. Place lid on jar; refrigerate at least 1 day. (Can be made 2 weeks ahead; keep chilled.)