1. Clean the lemons and limes. Add boiling water to all ingredients and allow to cool. You may scale up the ingredients to make a pitcher of three sour. I usually make 5 cup batches.
2. Strain ingredients and place in a glass and add ice. May garnish with lemons, and limes, and plums. I also squeeze all juice from lemons and limes.
Tip: You can adjust the sweetness by making a sugar syrup. Just boil one cup of water with one cup of sugar. You simmer the mixture while continually stirring. Once the sugar dissolves, then let the syrup cool.
Tip: Salty plums neutralizes the sourness of the drink.