1 Granny Smith apple, shredded
1/3 cup unfiltered apple cider vinegar
1/4 cup white sugar
1 teaspoon grated fresh ginger
Place apple in a glass jar with a tight-fitting lid. Add apple cider vinegar, sugar, and grated ginger; stir well. Close tightly. Let sit in the refrigerator, 4 to 5 days.
Strain syrupy liquid into a clean bottle, discarding apple scraps. Close tightly and chill.