Kakiage (vegetable Tempura) Recipe

Prepare batter base

Place the egg in a mixing bowl and lightly beat it just to combine yolk and white. Add the ice-cold sparkling water to the egg and stir gently. Keep the liquid as cold as possible (set bowl in another bowl with ice if desired).

Mix dry ingredients

In a separate bowl, whisk together the all-purpose flour, cornstarch, baking soda, and salt until evenly combined.

Combine to make batter

Briefly and gently fold the dry mix into the cold egg-water mixture. Do not overmix — small lumps are fine. The batter should be loose and slightly lumpy; if too thick, add the extra cold water 1 tablespoon at a time to reach a coating consistency (similar to heavy cream). Keep batter cold and do not beat vigorously.

Prepare vegetables

Thinly slice the onion, julienne the carrot, slice the shiitake caps, trim and cut the green beans into ~1" pieces, and thinly slice the scallions. If using grated potato as a binder, squeeze out a bit of excess liquid but keep some starch to help hold the mix together.

Combine vegetables

In a large bowl, toss all prepared vegetables together so they are evenly distributed. Lightly season with a pinch of salt (about 1/4 tsp) to draw out slight moisture and flavor.

Dredge and mix with batter

Working quickly, add 3/4 of the batter to the vegetable bowl and gently fold to coat — you want the vegetables moistened but not swimming in batter. Reserve the remaining batter for touch-ups when frying. The mixture should cling together when pinched; if too loose, add a small spoonful more of flour or the reserved batter as needed.

Heat oil

Pour oil into a heavy pot or deep skillet to a depth of about 2–3 inches (enough for shallow deep-frying). Heat to 350°F (175°C). If you don't have a thermometer, test with a small drop of batter — it should sizzle and rise steadily but not burn immediately.

Form and fry kakiage

Using two spoons or a small ladle, scoop about 2–3 tablespoons of the vegetable-batter mixture and form a loose patty (roughly 3–4 inches across). Gently slide the patty into the hot oil. Fry 2–3 patties at a time without crowding. Fry until the underside is golden (about 1.5–2 minutes), then flip and fry another 1.5–2 minutes until crisp and pale golden. Total fry time ~3–4 minutes per side depending on thickness. Adjust heat to keep oil between 320–350°F so kakiage cooks through without over-browning.

Drain and keep crisp

Transfer cooked kakiage to a rack or paper towels to drain briefly. For maximum crispness, place on a wire rack over a baking sheet in a 200°F (95°C) oven for a few minutes while you finish frying the rest, but avoid long holding which will dry them.

Prepare tentsuyu dipping sauce (optional)

Combine dashi (or water), mirin, and soy sauce in a small saucepan (adjust to taste; a basic ratio is 2 parts dashi:1 part mirin:1 part soy). Warm briefly — do not boil — then remove from heat. Serve with grated daikon on the side if desired.

Serve

Serve kakiage hot, with tentsuyu or soy sauce and a wedge of lemon or lime. They can be served on their own, over rice, or alongside soba/udon as a tempura topping.