Preheat oven to 425 degrees F.
In a large mixing bowl, drizzle oil over the potatoes and toss to coat. Add salt and taco seasoning mix and toss. Place sweet potato fries in one even layer onto a baking sheet. Keep space between them so they get crispy on all sides. Bake in batches.
Place into the oven for 10 minutes, then flip them over. Place back in for 10 more minutes. They should be soft on the inside and browned on the outside. Let them cool for 5 minutes before serving.
You may substitute baking potatoes for sweet potatoes. However, when placing back into the oven change cooking time to 5 minutes instead of 10.