Stem fully ripe Concord grapes. Wash thoroughly. Fill your favorite canning kettle, can be any size. Cover grapes just to the top of them with water. Simmer until grapes are mushy. Remove from heat and put into colanders, sieves, etc. Leave an hour or so while you wash jars, etc. or maybe watch your favorite "Soap"!
Measure juice and add 1/2 cup sugar per quart. Heat to boiling and seal in hot sterile jars. When opened for use, empty juice into a pitcher twice the size of jar. Next, fill jar with water. Stir and enjoy after adding water to juice.
Note: An added bonus from this recipe is the grape pulp can put through a Foley Food Mill and the pulpy juice can be used to make your jelly.