I found this recipe several years ago, I don't know where

Wash and stem 1 cup concord grapes for each quart of juice. Put grapes in each quart
jar. Afdd 1/2 c. sugar to each jar. Add boiling water to each jar. Seal and put in a
boiling water bath. When rready to serve, Pour contents of jar through sieve. Yoo may
neeed to add more sugar depending on the sweetness of the grapes.
This is delisious. And certainly the easiest way to make grape juice/