Preserved Lime (Nam Ngau) 12 fresh limes 8 to 10 cups of water enough to cover the limes 1/2 cup + 2 T of salt (it should be 4 T of salt for 4 cups of water)so adjust your salt and water to cover the limes.
Wash limes and let it sit under the sun for 3 days or longer, when the lime is ready Boil water add salt stir until the salt is dissolved. turn the heat off let cool In a big jar put the limes in add salt water to it.
It will take few weeks or month before the lime ready to use. When it ready keep in the refrigerator for months or years.
You can use preserved lime to make duck, chicken soup or drink when you have a cold.