How to Make Japanese Tempura

I was long very disappointed in the quality of my tempura as compared to that of our local restaurants, The Osaka and The Asuka. My disappointment was in the batter. I had tried rice and wheat flour. The restaurant’s comes out very light, bubbly and crunchy. Mine was rather heavier. The secret for me was simply ice cold soda water instead of plain water.

Vegetables, fish and seafood
  green beans ends trimmed leave whole
  carrots sliced diagonally about ¼" thick
  sweet potato peeled, sliced about ¼" thick
  zucchini sliced about ¼" thick
  button mushrooms halved if caps are too large
  onion rings or slices; toothpicks will hold slices together.
  white fish fresh, cut fillets crosswise into long or bite-sized pieces. Cook on disposable wooden spits for easy serving.
  shrimp shell and de-vein leaving tails attached. Lay shrimp flat and score 3 or 4 times across the belly to make it lay flat and prevent from curling when fried. This is especially useful when making tempura shrimp for use in sushi.

Tempura batter
  1½ cup sifted flour
1 cup ice cold soda water
1 egg yolk (optional only—some recipes use the white too)

The soda water is essential. Without it, the batter will be heavy and disgusting.

Despite the photos here, I do not usually use egg in my tempura.

Prepare vegetables and fish or seafood (as noted below) and dry thoroughly with paper towel. Do not prepare tempura batter until ready to cook (oil hot).

Heat oil in a thick pot, wok or deep fryer to 350°. Oil must be at least 2" deep.

In mixing bowl, lightly beat egg if egg is to be used. Pour in soda water mixing slightly. Add flour all at once and stroke a few times with a fork just until ingredients are loosely combined. Nota bene: The batter should be lumpy and not smooth. If over-mixed (until smooth), the gluten may awaken and the resulting coating may be heavy, oily and unpleasant after cooking.

Place 1 cup of flour on a plate, dredge the (dry) vegetables and fish in the flour then shake off excess. Dip in batter and lay in hot oil deep frying until lightly golden brown. Place on a plate covered with paper towel.

If the result isn’t as light and pleasant as you wish, don’t predredge the food. Skip the dredge and just dip in the batter before cooking. This is what I do. However, the recipe I started from used a) egg and b) predredging.

Fry vegetables first, then the fish or seafood.

Skim surface of oil occasionally to keep clean or break an egg into it, float it around to collect all the scraps, then lift out and discard. An écumoire is faster, easier and cheaper at this task.

Tempura sauce (for dipping)
  1 cup broth/stock
  ¼ cup soy sauce
  ¼ cup mirin*,
Serve with soy sauce in little bowls for dipping and a ball of sticky rice (a good brand is Nishiki) in a separate bowl.
Tempura presentation.
Scoring the shrimp so that it does not curl.
The prepared vegetables and shrimp.
Batter making: mixing the flour into the egg.
Dipping the shrimp in the tempura batter.
Frying dipped white fish.

* Mirin is a sweet rice wine used in Japanese cooking. Its alcohol content is around 8% to 15%. 1 teaspoon of sugar and 1 teaspoon of sake would substitute 1 tablespoon of mirin or, if no alcohol is desired, some of the flavor can be approximated using just a little sugar.