Place the oil in a frying pan or a wok and heat it to about 180˚C.
Cut your sweet potatoes into small strips and cut your cauliflower into small florets
Make the batter by combining the flour, corn starch, water, egg and salt and pepper
It's easiest to have some extra all purpose flour on a plate so you can roll the sweet potato through the flour first. Then add to the batter. Let any excess batter drip off
Add the potatoes covered with batter into the hot oil and wait for them to crisp up and become golden brown.