Rinse the grape leaves off in the sink. Drain the leaves and rinse them off again.
Pour 1 cup of kosher salt in a saucepan on the stove top. Add 4 cups of water and stir until the salt dissolves into the water. Bring the salt water to a boil.
Drop the grape leaves into the water. Place 12 leaves in at a time for best results. As soon as you drop them into the boiling water, remove the grape leaves and place them in ice water to blanch them. You do not want to allow them to stay in the boiling water or you will cook them for too long. Just a few seconds is all that's needed.
Dry the leaves off completely with paper towels.
Place the leaves flat and stack them into freezer bags. You can also stack the leaves, then roll them into a cigar shape and tie them with cotton string to create a bundle. A stack of six leaves works well to create a bundle.
Seal the freezer bags. Remove as much air as possible from the bags before you seal them.
Label the bags with a permanent marker. Write the contents and date on the bag. Store the grape leaves for up to six months.