Vegetable Tempura Recipe

Prep sweet potato

Peel the sweet potato and cut into 1/4-inch (6 mm) thick batons or rounds about 3 inches long. Aim for uniform pieces so they cook evenly.

Prep kabocha or pumpkin

Remove skin if desired and cut into 1/8- to 1/4-inch (3–6 mm) thin slices. Thinner slices cook quickly and become tender while staying crisp.

Prep mushrooms

Trim stems from shiitake and leave caps whole. If using larger caps, halve them so they are similar in size to other pieces.

Prep broccolini/asparagus & green beans

Trim tough ends from broccolini or asparagus, leaving spears whole. Trim and blanch green beans for 30 seconds in boiling water, then plunge into ice water to keep color and stop cooking; drain thoroughly.

Prep zucchini

Cut zucchini into 1/4-inch thick long strips or half-moons. Pat all vegetables very dry with paper towels; excess surface moisture will prevent batter adhesion.

Chill a bowl with ice or place bowl in an ice bath. Keep sparkling water and bowl very cold so batter stays chilled; this helps create a light, crisp crust.

In a medium bowl, combine 1 cup cake flour, 1 tablespoon rice flour, 1 tablespoon cornstarch, 1 teaspoon salt and 1 teaspoon baking soda (if using). Stir briefly to combine.

Lightly beat 1 large egg in a small bowl. Pour the ice-cold sparkling water (about 1 cup) into the beaten egg and stir gently to combine.

Add the wet mixture to the dry ingredients and mix with chopsticks or a fork just until combined. Do not overmix—some small lumps are fine. Keep batter cold by setting the bowl in the ice bath while you fry in batches.

Fit a large, heavy-bottomed pot or deep fryer with a thermometer. Pour in oil to a depth of 2–3 inches (about 1 liter) and heat to 350°F (175°C). Maintain 340–360°F (170–180°C) while frying.

Place 1 cup all-purpose flour for dredging on a rimmed plate. Working in small batches, lightly dust each vegetable piece in flour, shaking off excess. The thin flour layer helps batter adhere without absorbing excess oil.

Using tongs or chopsticks, dip each floured vegetable into the batter to coat lightly. Allow excess batter to drip off—aim for a whisper-thin coating, not a thick clump.

Carefully lower battered pieces into the hot oil, a few at a time so as not to drop the oil temperature. Do not overcrowd. Fry until batter is pale golden and crisp: thin items (green beans, broccolini, asparagus, zucchini) 1–2 minutes; mushrooms and kabocha/sweet potato slices 2–3 minutes. Adjust time based on thickness.

Use a slotted spoon or spider skimmer to transfer fried pieces to a wire rack set over a sheet pan or to paper towels to drain. If using paper towels, transfer to a wire rack briefly to keep bottoms crisp. Lightly sprinkle with flaky sea salt while still hot.

Keep finished tempura in a single layer on a warm plate or in a low oven (200°F / 95°C) on a rack to stay crisp while you finish remaining batches. Reheat briefly in a 350°F (175°C) oven for a couple minutes if needed; avoid microwaving.

In a small saucepan combine 1 cup dashi, 2 tablespoons mirin, 2 tablespoons soy sauce and 1 teaspoon sugar. Warm gently over medium-low heat just until sugar dissolves and mixture is hot but not boiling. Taste and adjust: add a little more dashi or water if too strong.

Serve sauce warm or at room temperature with grated daikon on the side for guests to add to bowls or spoon over tempura.

Arrange the tempura on a platter in single layers, grouping similar vegetables together so colors and shapes show. Place lemon wedges and small dishes of tentsuyu alongside.

Sprinkle a light pinch of finishing salt over select pieces, offer lemon to squeeze, and serve immediately to preserve the delicate, whisper-thin crisp exterior and tender vegetable interior.