Tempura with Prawns, Shiitake Mushrooms and Aubergine with a Dipping Sauce

The first thing you need to do is weigh out the cornflour, put it in a polythene bag and then place it with the unbroken egg in the fridge for about 1 hour to get thoroughly cold.

At the same time place a few ice cubes and about 3 fl oz (75 ml) cold water in a bowl or jug and put that in the fridge as well. Meanwhile, prepare the rest of the ingredients. De-vein the prawns: you can do this by inserting a cocktail stick in the centre of the back, digging down a little, then pulling the cocktail stick back and the little thread will pull out. In Japan they make a cross-like incision in the cap of each mushroom, which looks very pretty after cooking. Simply cut the aubergine slices into quarters.

Next prepare the dipping sauce. Grate the daikon radish finely, squeeze out the excess liquid in the palm of your hand, then place it in a saucer with the reconstituted wasabi.

When you're ready to cook the tempura, combine the two oils and begin to heat them, using a thermometer to check how hot it is getting. Have a plate with absorbent kitchen paper ready for draining and keep it in a warm place. When the oil reaches 175°F (90°C), take the chilled ingredients out of the fridge. In a bowl using chopsticks, blend the egg with 3 fl oz (75 ml) of the iced water, not too thoroughly – it's more blending than whisking. Now sift the cornflour, and what's going to be really hard now is to resist the temptation to whisk, but instead very lightly blend leaving some free cornflour unblended, and totally ignoring the lumps!

When the oil reaches 350°F (180°C), measure 1 heaped tablespoon of cornflour on to a plate – you're going to use this to coat the ingredients before they go into the batter. Begin with the prawns and, after coating with the cornflour, hold the tail of the prawn with cooking tongs, then quickly coat it with batter, and if this includes a lump, all the better. Now keep hold of the tail, lower the prawn into the hot oil and then release the tail about 30 seconds later. Now do the same with the second prawn and when they float to the top and the batter turns golden, they're cooked, so now remove them to the plate lined with kitchen paper to drain.

Now quickly cook the other 2 prawns and follow these first with the mushrooms, then the aubergines, all coated in cornflour and dipped in the lumpy batter first. You can put all 4 mushrooms in together and then all the aubergine in together. When you're ready to serve the tempura, add the soy sauce to the radish and wasabi. Mix together and use as a dipping sauce.