This is one of my favourite uses for preserving garlic and creates such a useful powder to have in the spice rack.i find It is great to use in a herb rub on a joint of meat for a Sunday roast or as a shaker to add a touch of garlic flavour to a meal.
I'm lucky enough to own a dehydrator which I use in this method but if you don't have a dehydrator you could always use an oven on a low heat with the door open.
I take one garlic bulb and peel away all to the cloves. These cloves I then slice to an even thickness (the thicker the cut the longer it takes to dehydrate). This does take quiet a while to do with a knife so using a food processor is quicker I find.
I then place these garlic slices on the trays in my dehydrator and turn it on after 3 or 4 hours they are dried to a crisp. These garlic chips can be stored and used as they are but to turn them into a powder I use a pestle and Morter and grind them to a fine powder (these does take a while and is quiet a workout). The smell of garlic from this is really quiet intense but pleasant.
This powder is now ready to store in a container suitable for dried herbs such as a small killer jar.
So there you have it please try it and let me know how you get on or what you find your uses for garlic powder are.