Peel and slice the sweet potato. You want thinner, long fries. They should be about ¼ inch wide.
In a large Ziploc bag, add sliced sweet potatoes and tapioca starch. Zip the bag and shake until everything is covered.
Add the oil to bag. Zip the bag and shake until everything is coated.
Add the salt and spices, zip and shake again.
Lay fries on lined pan in a single layer. Try to prevent the fries from touching each other. This will help ensure crispiness. Place in oven for 40-45 minutes.
Flip halfway through cooking. Check the fries after 35 minutes. If they are still soft continue to cook. Cook times can vary based on oven and type of pan your are using. For my oven and aluminum pan I usually have to cook the fries for a full 45 minutes.