Wash your sweet potatoes under cold water and then peel
Once peeled, CAREFULLY using your mandoline, slice your sweet potato lengthwise into thin strips
Once sliced, use a knife and cut them to about 1/4 inch thickness and set asideMelt your butter in a large saute pan over medium heat and add in all of your sweet potato "noodles"
Continually stir and cook until the sweet potatoes are cooked through to your liking, about 5 minutes for me
Sprinkle with your sage and cinnamon and mix well
Transfer to a plate and enjoy