In a bowl wide enough to fit the sweet potato slices, mix together the sugar and cinnamon. Thinly slice the sweet potato using a mandolin or sharp knife. Dip each slice into the sugar mixture and coat each side well. 

Place on a baking sheet lined with parchment, and bake for 10 minutes. Flip the chips over, and reduce oven temperature to 350 degrees and bake for 5-10 minutes more, checking often to avoid burning. 

Allow to cool and serve!