How to keep lettuce for one year?

The method of pickling lettuce is as follows:

Tools/materials: lettuce 1500g, salt, soy sauce, soy sauce, sugar.

1. After peeling off the old skin, wash the lettuce, drain the water, and cut it into lettuce strips with uniform thickness, or cut it into lettuce slices with uniform thickness.

2. Put the cut lettuce into a clean container, evenly sprinkle a proper amount of salt, mix well, cover it with a clean plastic bag, and then cover it with a heavy object for pickling 12 hours or more.

3. Drain the pickled lettuce, then rinse off the excess salt with boiling water and let it stand in the sun for about a day until the lettuce is slightly embarrassed.

4. Put the soy sauce, soy sauce and sugar into the pot, add water to boil, then turn off the fire and let it cool completely.

5. Put the dried lettuce in a clean container, pour in the fully cooled sauce without lettuce, and marinate for more than 24 hours before eating.