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If you grow organically, there’s no need to wash them but if you do, make sure the leaves are very dry. This ensures the herbs are dried—not steamed—in the oven.
Once it’s preheated, place your tray of herbs on the center rack and prop the door open slightly with a wooden utensil to allow some air movement. Then turn the oven off and let the herbs dry inside while the heat slowly dissipates.
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