Place blueberries, sugar, and red wine vinegar into sauce pan on stove top. Cook the mixture on medium high heat until the sugar dissolves, the blueberries soften, and the mixture thickens slightly.
Remove from heat and allow to cool. Transfer blueberry mixture to a clean mason jar and seal.
Refrigerate mixture for about a week, making sure to shake the glass every other day or so.
After a week, strain out the blueberries from the vinegar and return the vinegar to the glass jar.
Makes about 4 oz of vinegar.
Add 1-2 Tbsp of vinegar to 8 oz of carbonated water and stir.
Sweeten with a bit of vanilla simple syrup or add your favorite fresh herbs!