5 pounds of seedless grapes, washed and stems removed.
Pour mixture into mashed grapes and stir. Bring to a rolling boil until sauce begins to thicken. (About 5 – 10 minutes). Add 4 and 2/3 cups of sugar and stir. Cover and simmer 10 minutes. Remove from heat and add to jars sterilized in boiling water.
Screw on tops and add jars to a large pot of simmering water. This is to help kill any bacteria that may have entered the jar during the canning process and also to create an airtight seal.
Simmer jars for 10-15 minutes. You will begin to hear a pop come from each jar. This is the jar sealing. To be certain that each jar is completely sealed and ready for the pantry, press down on the middle of the jar lid with a finger. If the lid springs back then it is not sealed and refrigeration is necessary.