Wash oranges thoroughly to remove dirt and residue
Peel the oranges, removing as much white pith as possible
Cut the peels into small pieces
Spread the peel pieces in a single layer on a clean tray
Dry the peels completely in sunlight, a dehydrator, or a low-temperature oven
Check that the peels are fully crisp and moisture-free
Grind the dried peels into a fine powder using a blender, grinder, or food processor
Sift the powder to remove any coarse pieces
Grind the coarse pieces again if needed
Store the orange peel powder in an airtight container
Keep the container in a cool, dry place