Tempura Green Beans Recipe

Prepare green beans

Trim the stem ends of the green beans and rinse under cold water. Pat dry thoroughly with a clean kitchen towel or paper towels — moisture will cause the oil to spit and make the batter fail to crisp.

Heat oil

Pour 3 to 4 cups of vegetable oil into a deep, heavy pot or deep-fryer to a depth of about 2–3 inches. Heat over medium-high until oil reaches 350°F (175°C). If you don't have a thermometer, test by dropping a small pinch of batter into the oil — it should sizzle immediately and float.

Make tempura batter

In a medium bowl, whisk the egg lightly. Add the ice-cold sparkling water and stir to combine. In a separate bowl, sift or whisk together the all-purpose flour, rice flour, baking powder, 1/2 tsp of the sea salt, and 1/2 tsp ground black pepper. Add the dry mix to the wet in two additions and stir gently with chopsticks or a fork — do not overmix. The batter should be slightly lumpy and thin; if it seems too thick, add 1–2 teaspoons more ice water. Keep the batter chilled over a bowl of ice if possible.

Fry the beans

Working in small batches (6–8 beans per batch depending on pot size), dip each green bean into the batter to coat lightly. Shake off excess batter and gently slide beans into the hot oil. Fry until the batter is crisp and pale golden, about 1.5–2.5 minutes per batch. Avoid crowding the pot to maintain oil temperature. Use a spider/skimmer to turn and lift the beans for even cooking.

Drain and season

Transfer fried beans to a wire rack set over a baking sheet or to a plate lined with paper towels to drain. Immediately sprinkle with the remaining 1/2 tsp sea salt and remaining 1/2 tsp ground black pepper while still hot. If oil temperature drops below 325°F, let it come back up to 350°F between batches.

Keep crisp

If making ahead for service, keep finished tempura in a single layer on a warming tray or in a low oven (200°F/95°C) for no more than 10–12 minutes to stay crisp. Do not cover tightly, which will trap steam.

Combine Dijon mustard, hot mustard, mayonnaise, honey, rice vinegar, soy sauce, sesame oil and sriracha (if using) in a small bowl. Whisk until smooth and uniform. Taste and adjust: add up to 1 teaspoon more honey if too sharp, or a splash more rice vinegar if you want brighter acidity.

If the sauce is too thick for dipping, thin with up to 1 teaspoon of cold water, then season with 1/4 tsp fine salt and 1/4 tsp freshly ground black pepper. Chill until ready to serve; the flavors meld after 10–15 minutes.

Place a small bowl of spicy mustard sauce on the serving plate. Arrange the tempura green beans in a loose pile next to the sauce.

Sprinkle toasted sesame seeds and thinly sliced scallions over the fried green beans. Serve immediately with lemon wedges on the side for squeezing over the beans if desired.