Seven Day Preserved Lemons (Hamid Msyiar)

Makes 6 evenly spaced lengthwise incisions with a sharp, thin bladed knife through peel of each lemon, taking care not to cut into pulp. Heat lemons, water and salt in Dutch oven to boiling; boil until peels are slightly softened but lemons are still firm, about 8 minutes. Remove lemons from cooking liquid with slotted spoon; pack loosely into 3 1-quart jars. Cool cooking liquid to room temperature. Pour over lemons to cover. Cover jars tightly. Let stand 7 days at room temperature before using. Lemons can be stored unopened at room temperature up to a month. Opened jars can be stored tightly covered in refrigerator up to 2 months.