Preheat oven to 400 degrees. Cut potatoes according to your desired thickness or thinness. For these, I first cut the sweet potatoes in half, lengthwise, in order to have some stability when slicing into them. These fries were about one inch thick before baking, and as long as the original length of the sweet potatoes from which they came.
Spread cut fries onto a non-stick baking sheet in a single layer. Sprinkle sea salt and black pepper over potatoes then drizzle with olive oil. Alternatively, you can sprinkle with black pepper only and add sea salt to the fries when finished baking.
Toss fries in pan until evenly coated with olive oil, salt, and pepper. Bake for 25 minutes, or until fries reach your desired crispness (the baking time will be shorter for thinner fries).