Pre-heat an oven to 225°C/ 435°F and line a baking sheet with parchment paper.
Wash the sweet potatoes and cut it into 50x50 mm - 2"x2" fries. The more evenly you cut them, the more even they will cook. So try and be tidy (or not).
I like to leave the skin on because I'm lazy and I like the added texture but feel free to add extra work if that's your thing and peel your potato before you cut it into fries.
Place the fries into a bowl of cold water and let them sit there while you mix your spices.
Mix the spices with the cornstarch. DO NOT ADD THE SALT.
Strain and towel dry the fries.
Place the dried fries back into the (dried) bowl, slowly drizzle with roughly 2 T - 30 ml of oil and mix together so all the fries are coated evenly. You may not need all of the oil.
Sprinkle your fries with a thin layer of the cornstarch/ spice mix, making sure the fries get evenly coated.
Place the fries on your baking sheet in a single layer. Make sure none of the fries are touching. Make sure your fries have breathing room or they won't crisp up.
Bake your fries in the oven for 30-45 minutes. Turn the fries every 10-15 minutes until they are crisp (or crisp enough, because well really now...). Remove smaller fries if they're done cooking sooner and have a little pre-nibble if you want.
Season your fries with salt before serving.
Notes
Times and temps may vary, depending on your oven. You'll have to test what works best for you.
Keyword fries, full proof recipes, oven baked, side dish, side dishes, sides, sweet potato