This was in Gourmet a few years ago. You’ll never run out of fun things to do with these taste-filled citrus bombs. To prepare for eating/using in dishes, remove the inside part of the lemon (the part you’d normally eat) and throw away. You use the peel from this. I usually use organic lemons with that in mind.
2/3 cup kosher salt
1 to 1 1/2 cups fresh lemon juice (from 5 to 6 additional lemons)
2 tablespoons olive oil
Blanch lemons in boiling water 5 minutes, then drain. When cool enough to handle, cut each lemon into 8 wedges, discarding seeds. Toss lemons with kosher salt in a bowl, then pack lemons, along with their salt, tightly into glass jar with tight lid.
Add enough lemon juice to cover lemons. Seal jar and let lemons stand at room temperature, shaking gently once a day, for 5 days.
Add oil to jar and refrigerate. Preserved lemons can be chilled, covered in their juices, up to 1 year.