Preheat oven to 200 degrees. Place wax paper into a cookie sheet and spray with cooking spray.
Wash and slice the zucchini about 1/4 inch thick.
Put the sliced zucchini into a bowl. Drizzle with olive oil, salt and pepper to taste.
Lay the sliced zucchini in a single layer on the wax paper.
Bake for 2 hours. Check about ever 30 minutes. You may need to bake longer if the chips are still moist.
You can store in an airtight container for a week or two.