Step 1

Preheat oven to 110C/90C fan forced. Sift the flour, cornflour and bicarb into a large bowl. Sifting the flours aerates the dry ingredients and results in a lighter batter. Make a well in the centre.

Step 2

Whisk together water and egg in a jug. Add the egg mixture and ice cubes to the flour mixture and use chopsticks to mix until just combined. Do not over-mix – the mixture should still look lumpy.

Step 3

Heat oil in a wok or large saucepan over medium-high heat to 170°C on a cook’s thermometer. To test if oil is ready, add a cube of bread. If it turns golden in 20 seconds, the oil is hot enough.

Step 4

Use chopsticks to dip the sweet potato slices into the batter to coat. Deep-fry for 3 minutes or until the batter is crisp and potato is tender. Transfer to a large baking tray lined with paper towel to drain.

Step 5

Dip zucchini into batter and deep-fry for 2 minutes. Transfer to the lined tray. Dip capsicum and asparagus into batter and deep-fry for 1 minute. Place all the vegies on a wire rack over a baking tray. Place in oven.

Step 6

Dip half the prawns into the batter and deep-fry for 3-4 minutes or until crisp and cooked through. Transfer to prepared tray. Repeat with remaining prawns. Serve the tempura with soy sauce for dipping.