Heat the oven to 400° convection (if able).
Wash and peel the vegetables.
Using a box grater, grate the vegetables until you have roughly 4 cups total.
Pour the grated vegetables into a clean tea towel and wring out any water/moisture. These vegetables have a surprising amount of water so be sure to squeeze thoroughly!
Pour the squeezed vegetables into a bowl.
Add the chopped onions, garlic, salt, pepper and 1 tbsp oil. Mix thoroughly.
Drizzle a sheet pan with remaining 1 tbsp oil.
Pour the vegetable mixture onto the sheet pan and spread evenly.
Bake for 15 minutes, remove from the oven and stir. Spread out mixture again and bake for an additional 15 minutes.
Remove from the oven and stir again. If it needs additional time, cook for an additional 7-10 minutes, checking for your preferred crispiness.
Enjoy immediately or save leftovers for up to 3days in the fridge. Reheat in the oven or by pan-frying for best results.