A few weeks ago I got a really good deal on organic lemons - I had NEVER seen them priced that low. I stocked up on a lot. First thing I did was (after washing them) zest a few to freeze for later use. Then I sliced the rest and laid them on parchment paper on a baking sheet. I then froze them. I keep them in a zippered bag in the freezer and can take out a slice for my glass of water or make a larger jar with them.