Wash the potatoes, then cut them lengthwise into 1/2" thick slices. Then cut each slice lengthwise into 1/4" sticks. Fill a large bowl with cold water and soak the potato slices for about 1 hour. Drain the potatoes and pat them dry with paper towels.
Preheat oven to 425ºF. In a large bowl, toss the potatoes with canola oil to coat. Mix the cornstarch, smoked paprika, salt, black pepper, cumin, and garlic powder in a small bowl, and add to the potatoes. Toss until potatoes are evenly coated in the seasoning mixture.
Place potatoes in a single layer on 2 parchment-lined baking sheets and bake for 40 minutes, flipping the potatoes halfway through. Check the potatoes and continue baking another 5-10 minutes until desired crispness is reached. Serve with your favorite dipping sauce.
Bake time will depend on your oven, how thick you slice the potatoes, and how much you crowd the baking sheets. Keep a close eye on the potatoes after 40 minutes, as they can burn quickly!