Separate the cloves from the main bulb and remove the outer papery skins, exposing the fresh garlic.
Place the garlic cloves into the blender or food processor and pulse until they become finely minced into a thick, spreadable puree. This method crumbles well after freeze drying; you can make it into garlic powder or crumbled pieces. Homesteading Hack: You can freeze dry whole garlic cloves, but they become rock hard and are difficult to process into powder. If you decide to keep them whole, smash each clove so it is thoroughly freeze dried all the way through. Slivered garlic will freeze dry and rehydrate but requires more prep and drying time.
Line your freeze dryer tray with the optional parchment paper, and spread the garlic puree evenly over the tray about an eighth inch thick.
Place the tray of pureed garlic into the freeze dryer and freeze dry for 16-22 hours. Test it by crumbling it in your hands to make sure it has dried completely. If the garlic is not fully dry, or feels cold to the touch, place it back into the freeze dryer for two-hour increments until thoroughly dried.