Pick and prep: Choose fresh scallions with no slimy spots. Trim off the root ends and any wilted tips.

Wash well: Rinse under cool water, lifting the layers to remove grit. If they’re very sandy, soak for 2–3 minutes in water with a splash of vinegar, then rinse and pat dry.

Decide your cut: For quick drying and pretty flakes, slice thinly across the stalks (about 1/8 inch). For a chive-like sprinkle, slice only the greens. For a stronger onion note, include more of the whites.

Separate by color (optional): The white parts hold more moisture and dry slightly slower. If you want even drying, keep whites on one tray and greens on another.

Arrange for airflow: Spread slices in a single, loose layer on dehydrator trays or parchment-lined baking sheets. Avoid clumps; they trap moisture and slow things down.

Dehydrate, not cook: Dehydrator: Set to 95–115°F (35–46°C) for delicate greens or up to 125°F (52°C) if your space is humid. Dry 3–6 hours, checking at the 3-hour mark.

Oven: Set to the lowest temp (ideally 170–200°F / 75–95°C). Prop the door slightly open with a spoon for airflow. Dry 2–4 hours, stirring once or twice.

Air fryer with dehydrator mode: Use 120–140°F (49–60°C). Layer thinly and dry 1.5–3 hours, shaking gently midway.

Test for doneness: They should feel crisp and papery, not leathery. A piece should snap cleanly. If it bends, keep drying.

Condition the batch: After cooling fully, place the dried scallions in a clean jar 2/3 full. Seal and shake once a day for 3–5 days. If you see fogging or clumps, there’s residual moisture—return to the dehydrator.

Store properly: Once conditioned, keep in an airtight container away from light and heat. Label with the date.

Optional finishing: Blitz a portion in a spice grinder for scallion powder. It’s fantastic for rubs, dressings, and compound butter.