2 cups sugar
1 cup distilled white vinegar
6 cups mangoes
1 medium onion, chopped
1/2 cup golden raisins
1/4 cup crystallized ginger, finely chopped
1 garlic clove, minced
1 teaspoon mustard seeds, whole
1/4 teaspoon red chili pepper flakes
Combine sugar and vinegar in a 6 quart pot; bring to a boil, stirring until sugar dissolves. remaining ingredients and simmer, uncovered, until syrupy and slightly thickened, 45 minutes to 1 hour. Stir occasionally during cooking.
Pour into clean, hot jars leaving 1/2-inch headspace; close jars. .