Peel the onion and garlic as you normally would.
Thin-slice your onions and garlic.
Using a food dehydrator, place the slices or dices in a single layer on the food dehydrator sheets.
Dehydrate overnight and check for doneness. They will be done when they are completely crispy.
When done, grind into a fine powder in a blender or food processor.
Store in a container with a tight-fitting lid, best in a cool, dark, and dry area.