Start with 1 ripe pineapple.

Lay pineapple on its side, on top of a cutting board. Using a sharp chefs knife, cut off the top and bottom of the pineapple. Stand pineapple up on its end.

Cut the skin (and spiky things) off the sides in strips, continue around the pineapple until all the skin is removed. Cut pineapple with a mandolin slicer (using the thick setting) or cut in 1/4 - 1/8" slices using a good knife. Once you have sliced the pineapple, remove the core by punching the center with a small cookie cutter, about a 1" round. You can also use a knife to cut it out.

Lay pineapple rings, not touching on your dehydrator trays (mine holds 9 rings per tray). Repeat until you have filled your whole dehydrator. Mine takes 5 pineapples (with a little snacking). Fill your dehydrator and dry according to your manufacturers instructions.

Alternately you can lay on baking sheets and bake in oven at 165 degrees for 6-16 hours until leathery and not sticky.