If you have a deep fryer, pour oil into it and heat it to 170°C.
Alternatively, pour vegetable oil for frying into a heavy-bottomed deep pan and heat to 170°C. (You can check the temperature with a laser thermometer, or if you don’t have one, drop a cube of bread into the oil—it should turn golden in 20 seconds.)
Place the sliced root vegetables of one type into the oil and fry until cooked and golden. They should be crispy on the outside and soft on the inside.
Transfer them onto paper towels to absorb excess oil. Then, place them in a large paper bag, add the spices, and shake well. Serve hot.