1Heat oven to 400°F. Cut sweet potatoes into very thin slices. In large bowl, toss potatoes with oil, salt and pepper. Place potatoes in single layer on 2 ungreased cookie sheets (slices can touch but not overlap).
2Bake 10 to 15 minutes, rotating cookie sheets once, until edges are crisp but potatoes are still soft in the center. Cool 5 minutes; remove from cookie sheets to cooking parchment paper. Cool completely (chips will become crisp as they cool).