Scrub sweet potato well, cut off the ends, and trim off any brown spots. Using the thinnest blade on a mandoline, slice sweet potato into very thin slices (see note). Be careful of your fingers!
Put the slices in a bowl and add oil, salt and pepper. Toss to coat. I use my hands to make sure each slice is lightly coated with oil.
Cut out a piece of parchment paper in a circle to fit the glass turntable in your microwave. Arrange sweet potatoes in a single layer on the paper. They won't all fit at once, you'll have to microwave them in batches.
Microwave on high power for 3 ½ to 4 minutes or until crispy but not browned. Watch carefully for the first batch or two to determine the proper time since all microwaves are slightly different. 3 ½ minutes was my perfect number. Repeat this step until all chips are cooked.
Best served immediately.
Video
Notes
If you don't have a mandoline, use a large sharp knife to very thinly slice the sweet potato. The slicing side of a box grater is another alternative.
The sliced sweet potatoes (pre-cooked) can be stored in a bowl of water in the fridge. Drain and pat dry before adding oil.