Begin by cutting the renkon, aubergine, carrot and sweet potato into rounds and the pumpkin into crescents. The vegetables shouldn’t be more than a centimetre thick to ensure fast cooking. Remove the shell of the prawns leaving the tail attached.
Pat the ingredients dry with a piece of kitchen paper, place on a plate and keep in the fridge prior to cooking. Chilled ingredients are important to help form a crispy tempura batter.
Now grab a heavy bottom pan and fill it approximately 2/3 with oil before heating to 160-170°C (you could use a deep fat fryer to regulate the temperature). A thick pan is best to retain the temperature, an iron wok is even better. Check the oil is at the right temperature by dropping a splash of batter into the oil. If it sizzles the oil is ready.
Mix 200g tempura flour with 320ml iced cold water to make the batter. The colder the batter and ingredients before frying, the lighter and crispier your tempura will be. You can use ice cubes to keep your batter extra cold.
Dust the ingredients with a little flour, then dip into the batter, covering completely.
Place the battered ingredients with your chopsticks into the oil and cook for a minute or so on each side until the batter turns golden. Don’t cook too many pieces at one time as it will lower the oil’s temperature.
Remove from the pan and place on a wire rack. Remove any excess oil by placing on kitchen paper and serve whilst piping hot with the tsuyu dipping sauce made according to the bottle’s instructions (usually 2 parts water for every 1 part stock).
• You can also try making tempura with any other vegetables or seafood. Meat is not commonly used for tempura but if you want to add it to your ingredients just slice it very thinly as it will be easier to deep-fry.
• Serve with a bowl of sticky white rice on the side. You can also make Tempura Don by using tempura as a topping on rice, or use some as a crispy topping for ramen noodles.
• It is better to make the batter mix just before deep-frying. Mix the batter as little as possible, making sure there are no lumps. This prevents the gluten in the flour from stretching, ensuring that the batter is not chewy and is as light and crispy as possible.
• If you have any left over vegetables or batter you can make Kaki Age style tempura. Slice the vegetables finely then mix them into the batter, spoon into the oil and fry as normal.