3 1/3 cups live vinegar, which contains living yeast (look for the words “unfiltered” or “organic” on a label)
3 cups maple syrup
1 1/3 cups dark rum
Pour vinegar into a large glass or plastic container with a loose-fitting lid. Mix in maple syrup, dark rum and 7/8 cup water. Cover the opening with cheesecloth to keep out dust and allow for airflow so that wild yeasts can find their way in. Place the lid gently on top and store in a cool, dark place for 4 weeks. When it tastes smooth, tart and sweet, with no alcohol burn (this might be in 4 weeks, or it may need more time), the vinegar is ready. Strain it into smaller containers and store at cool room temperature, or in the refrigerator.