I bought a few yellow and a few red onions at the Wyandotte Farmer's Market, and along with some garlic, I dehydrated them outside. I want to point out the outside part, because when you use fresh onions, they are much more potent than onions sitting on a store shelf for awhile, and when you dehydrate them, they will smell up a house and make you tear up something horrible. When you plan on dehydrating onions, pick a nice day, where you can have the dehydrator outside , or in a garage, for the first few hours.
A few yellow and red onions from Wyandotte
I have 7 trays on my dehydrator, so I only cut up enough onions and garlic to fill just that many trays. You don't want to cut up onions and sit them in the fridge because they start to take on a nasty taste and texture after a day or two. These five onions filled up four trays, and the garlic filled up three. I have already done a post on drying garlic, so please check that out if you are interested in doing garlic.
Onions in dehydrator
I like to slice the onions with my mandolin slicer, about 1/4 inch thick. I also like to mix my onions, but this is a personal preference. Once all the onions are sliced, and my eyes are dry enough to see, I take the whole operation out onto the deck, under my umbrella. I then lay the slices out on the dehydrator and set it at 135.F. If you separate the rings, the onions will dry faster, but you can leave them as whole slices also. If I have time, I will separate every other ring, so that the small rings are inside the big rings, but not touching. If I have things to do, I just throw them on whole and be done with it.
outside on the deck
Now, just to let you know, the fresh onions are potent, so much so, we have to make sure all the windows facing the back yard are closed, because the onion will drift in. My husband's office window was open this day, and he came down all blurry-eyed, asking me what I was cooking, because the onion was going to overwhelm the entire dish. The neighbor came over to pick up her daughter, and could smell it from the driveway! Now, this onion-y-ness will last a few hours, but when it started to get dark, I was able to bring the operation back in, and finish through the night with no trouble.
Mezza Luna and dehydrated onions
Tho onions and garlic are done when they are crispy, and will chop up easily. Once the onions are done, I place them in a bowl for a few minutes to cool off. I like to use my Mezza Luna to mince the onions, but you can use a spice grinder on course. I also like to add a large pinch of kosher salt to the minced onions, mostly for moisture control.
Dried Minced Onions
If you want to make onion powder or onion salt, you can use a spice/coffee grinder. With onion salt, add kosher salt to the onion slices and grind on course while pulsing the grinder. For powder, grind on fine until it is a powder.
You will want to process your onions as soon as they are cool, and once your spices are done, keep them in an airtight storage container or bag. Onions like to suck up moisture, and if left out in the open, they will draw in all kinds of moisture and can go bad.
Minced Onions and Garlic Chips
Here are the finished projects. The garlic chips will be used in sauces and soups, instead of being turned into spices, and the onions will be used when I want fresh onion taste, but really don't have the time or inclination to chop up a fresh one. I will turn some more into powder when I make my sweet potato chips!