Vegetable Tempura Recipe

Prepare ingredients cold

Place a metal or glass bowl and the sparkling water in the refrigerator or freezer for 5–10 minutes to chill. Keep the egg cold until ready to use. Cold batter gives a lighter, crispier coating.

Crack the egg into the chilled bowl and lightly beat it with a fork until just combined. Do not overbeat.

Add the chilled sparkling water to the beaten egg and stir gently to combine. Keep the mixture bubbly; do not whip out the carbonation.

In a separate bowl, sift together the all-purpose flour, cornstarch, and salt. Make a small well and pour the egg-sparkling water mixture into the flour.

Using chopsticks or a fork, very briefly mix the wet and dry ingredients just until a few streaks of flour remain. The batter should be lumpy and slightly thin — do not overmix or develop gluten.

Return the batter to the refrigerator for up to 10 minutes while you prepare the oil and vegetables. Keep it cold; if it thickens, gently stir in a tablespoon of ice water to loosen.

Prepare all vegetables so they are dry and uniformly sized to ensure even frying: slice sweet potato into 1/4-inch rounds or half-moons; cut zucchini into 1/4-inch sticks or rounds; separate broccoli into small florets; trim green beans; core and slice red pepper into strips; halve or trim mushrooms.

Pat all vegetables thoroughly dry with paper towels. Excess surface moisture causes oil to spit and makes the batter less crisp.

For denser vegetables (sweet potato, carrot if using), par-cook by blanching in boiling water for 1–2 minutes then plunging into ice water to stop cooking. Drain and dry completely before battering. This ensures they cook through without over-browning the batter.

Pour the neutral oil into a deep pot or heavy-bottomed pan to a depth of about 2–3 inches (enough for shallow-deep frying). Heat over medium-high until the oil reaches 350–375°F (175–190°C). If you don't have a thermometer, test by dropping a small amount of batter — it should sizzle and rise immediately without browning too fast.

Working in small batches (3–5 pieces at a time depending on pan size), dust each vegetable lightly with a bit of flour to help the batter adhere. Dip each piece into the chilled tempura batter, letting excess drip off gently — you want a thin, airy coating.

Carefully lower battered vegetables into the hot oil using tongs or a slotted spoon. Do not overcrowd the pan, which will lower the oil temperature and make the coating soggy.

Fry until the batter turns pale golden and crisp, about 2–3 minutes for thin vegetables and 3–4 minutes for thicker pieces like sweet potato. Turn pieces if necessary for even browning.

Use a slotted spoon or spider to remove the tempura and drain on a wire rack set over a baking sheet or on paper towels. Keep finished pieces in a single layer in a warm (200°F / 95°C) oven for a few minutes if needed while you finish remaining batches.

If the oil temperature drops too much, let it recover to 350–375°F before frying the next batch. Maintain consistent oil temperature for best results.

Make a simple dipping sauce (tentsuyu): combine rice vinegar, soy sauce, mirin (or 1 tsp sugar dissolved into the dashi/water), and dashi or water in a small bowl. Taste and adjust: it should be balanced—lightly sweet and salty with mild acidity.

If using grated daikon, mix a small spoonful into the dipping sauce or serve it on the side for diners to add as desired. Provide lemon wedges as an optional brightener.

Serve the tempura immediately while hot and crisp, arranged on a platter with the dipping sauce. Recommend 2–3 pieces per person as an appetizer or 6–8 pieces as a main component.