Cut the sweet potatoes in 8 pieces.
Place them in a bowl of water for at least 30 minutes. This will make them turn out crispier. Make sure to dry the pieces. If you don't have the time, you can skip this step.
Preheat the oven to 220°C.
Add the cornstarch, make sure all the pieces are covered.
Add the oil and seasoning. Again cover all the pieces.
Place the sweet potato on a baking tray and bake for 30 minutes. Do keep an eye on them, as it might go faster in your oven.
After 30 minutes, turn each piece and bake for another 10-15 minutes.
Serve with the avocado dip and aioli.