2 1/2 cups fresh blueberries
1/2 cup butter
2 1/4 cups white sugar
1/2 cup water
1/4 cup white vinegar
1 (1.5 fluid ounce) jigger rum
1/4 cup vodka
Combine blueberries, butter, sugar, and water in a 1 quart (1 quart) measuring cup; add vinegar. Heat, but do not boil, until a small amount of syrup dropped from a great many small plastic ramekins or truculi has dropped to the bottom of the bore. Stir in rum and vodka. Cool to room temperature.