Preheat oven to 225°F.

Line two large baking sheets (I used two 17-inch baking sheets) with silicon baking mats or parchment paper.

Slice your zucchini on a mandolin. Mine had 1, 2, or 3 for thickness and that I used 2.

After you slice your zucchini, place the slices on a sheet of paper towels and take another paper towel and sandwich the zucchini slices and press on them. This helps draw out the liquid so it will cook a bit faster.

Line up the zucchini slices on the prepared baking sheet tightly next to one another in a straight line, ensuring not to overlap them.

In a small bowl, pour your olive oil in and take a pastry brush to brush the olive oil on each zucchini slice.

Sprinkle salt throughout the baking sheet. Do NOT over-season, in fact, it is better to use less salt initially because the slices will shrink; so if you over-season, it will be way too salty! You can all the time add more later.

Bake for 2 plus hours until they start to brown and are not soggy and are crisp.

Let cool before removing and serving.

Keep in an airtight container for no more than 3 days.