I didn't think it could be done... a substitute for pepperoni?! But it totally worked and was incredibly easy!!
Just thinly slice sweet potatoes and put them in a ziplock bag with enough olive oil to lightly coat the surface.
Then, add (sorry, no idea with the ratios.... )
sea salt, black pepper, smoked paprika, ground red pepper, crushed red pepper, and fennel until the sweet potatoes are well seasoned.
Zip up the bag and toss around until evenly coated. Add sweet potatoes to the top of an unbaked pizza and cook until soft and slightly golden.
VOILA!! They taste deliciously similar to pepperoni and actually give you antioxidants that fight disease! BOOYA!