Rinse lemongrass stalks under cool water and pat very dry with towels.

Trim both ends of stalks. Cut off and discard any dried out or woody upper portions, keeping just the smooth lower 5-6 inches.

Peel away any outer tough layers with your fingertips until reaching the softer inner core.

Slice stalks crosswise into thin rounds about 1/8-inch thick.

Chop sliced lemongrass very fine into smaller pieces.

Spread pieces in a single layer on dehydrator trays or baking sheets. Dehydrate at 95°F - 115°F, until completely dried and brittle. Time ranges from 8-24 hours depending on method.

Working in small batches, grind dried lemongrass into a fine powder using an electric spice grinder or food processor. Avoid over-processing.

Sift out any fibrous pieces. Combine powder batches and store in an airtight container in a cool, dark place for up to 6 months.