What you will need:
There is really no right or wrong way to prepare your food before you dehydrate it but you can pre-treat it if you want to. I will be doing a post for how to do this.
First thing you need to do is peel those onions. Remove the root, top and skin. Save and freeze the skins to use when making Chicken or Beef Stock. Slice in 1/4 inch slices, 1/8 inch rings or chop. I chopped this batch.
I sliced my onions and then chopped them in a food processor for just a minute. Make sure you don't liquify them.
Spread the chopped onions on your trays and dry at 145 degrees for 4 to 8 hours. Onions are leathery when done.
There are non stick liners that you can get to fit your trays, but I didn't use them.
If you don't have an Excalibur, don't worry. I used a cheaper dehydrator with no fan for a long time before I was finally blessed with mine.
These onions are great for using in cooked dishes like Meatloaf, Chili, Spaghetti. It's not necessary to re-hydrate before using them in cooked dishes.
They are easily re-hydrated. Just cover in boiling water and soak for 5 to 20 minutes.