You'll need a clean jar, lemons, salt and lemon juice.
Scrub lemons to remove wax coating. Ideally use unwaxed lemons if you can get them. Slice into quarters leaving one end attached.
Place a tablespoon of rock salt into centre of lemon and place in jar. Cover with lemon juice and seal. (I would normally squeeze lemons for this but today have taken the easy way and used bottled juice.) Store in a cool dark cupboard for 1 month. To use rinse lemon quarter and remove pulp. Cut peel into slivers and use in recipe.
It was after I started making these I discovered I didn't have a jar big enough to take more than one lemon.
Others have made preserved lemons and written far more detailed recipes.
Elise
Sam
David
Heidi