Ingredients
* some vegetables
* 250 ml ice cold water
* 250 g plain flour
* 150 g cornflour
* some oil , for deep frying
* 200 ml Dashi
* 60 ml mirin
* 40 ml soy sauce
* some ginger , to garnish
* some daikon- Japanese white radish , to garnish
* 1 pinch of salt
* 1 freezer bag
Method
Chill ingredients: Before you begin, put 200 grams or 7oz of plain flour, and 150 grams or 5.3 oz of corn flour together in an airtight bag and place it in the freezer. Cooling these ingredients will help to keep the tempura batter light.
Make the sauce: First add 200 millilitres or 7fl oz of dashi and turn the heat on low. Then add a pinch of salt, 60 millilitres or 2.1 fl oz of mirin and 40 millilitres or 1.4 fl oz of soy sauce. Stir gently. As soon as it begins to simmer turn off the heat and leave it to cool while you make the tempura.
Chop the ends off the asparagus, if it is not ready prepared. Cut the onion into semi-circular pieces. Spear each piece with a cocktail stick - this will stop the rings from separating as they cook. Chop the pepper into quarters and remove the insides and seeds. Slice into small, bite-sized portions.
Take the fresh ginger and carefully peel about 2cm, or just over half and inch, from one end. Then finely grate this section. A normal grater is fine. Next take the Daikon, that's the Japanese white radish. Cut off a reasonable sized chunk, peel, and grate. Now put the ginger and Daikon to one side.
Get the chilled flour mixture out of the freezer and tip it into a mixing bowl. Take 250 millilitres or 8.8floz of water. Add a little to the flour and roughly mix with chopsticks, or a fork. Add the rest of the water a little at a time. Be careful not to over-mix - the lumps give tempura it's unique texture.
Heat the oil: You can use any deep heavy bottomed pan or wok. Fill the pan about 2 inches deep with oil - there needs to be enough oil to fully cover the tempura pieces once they are in the pan. A tempura pan has a special lid that prevents the oil from splashing out, so if you don't have one, be sure to be very careful. Put the pan on the hob over a high heat. It will take about 10 minutes for the oil to reach the right temperature. To check if the oil is hot enough, drop in a little of the batter mixture. If it doesn't rise quickly it's not hot enough. It should bounce back up to float at the top of the oil.
Dip each vegetable piece first in a little plain flour, then in the batter, making sure that it is completely covered. Then use a chopstick or whatever you are comfortable with to place it in the oil. Repeat this process for all of the vegetables. Put the smaller vegetables, in this case the asparagus, in last as they take less time to cook. Don't cram the vegetables in - each piece needs to be able to float freely. Move them about frequently to make sure that the tempura is covered in oil and cooked evenly. Once they have turned golden brown, which should be after about a minute, they are cooked.
Remove them from the pan one by one, shaking off any excess oil as you go, and place them on some paper towel.