Line a rimmed baking sheet with parchment or a silpat. Pro tip: place a baking rack under the parchment to keep the cherries from rolling around while you're transferring the baking sheeting to the freezer.
Pit your cherries.
If you're freezing any Rainier cherries, soak them in a bowl of water and 1/4 cup of lemon juice for 10 minutes before straining.
Add the cherries to the baking sheet and place the tray in the freezer. Pro tip: If you have a lot of cherries to freeze at once, lay another piece of parchment on top of the cherries and top with an additional layer of fruit.
If you had to cut your cherries to remove the pit, lay them halves cut-side down on the baking sheet to prevent rolling.
Freeze for about six hours.
Break apart any clumps that have formed on the baking sheet and transfer the cherries to freezer-proof storage.
Notes
They'll keep in the freezer for 6-12 months.If you use frozen cherries in baked goods, there is no need to defrost them first!