I buy fat lemons whenever I see them in local markets or the local supermarket. I give the jars of these preserved lemons to friends but keep at least two for myself and use them in Moroccan stews but mostly in all sorts of otherwise, ordinary chicken dishes. I always wash the lemons in warm water and give them the once-over with a clean pan scrubber. Also, I use my favourite olive oil. You need Kilner type 1-litre jars which need to be sterilised by putting them, detergent free, in the dishwasher on the fastest cycle.
Sometimes bay leaves, peppercorns and other spices are added but I think these additions detract from the lovely, pure citrus tang.