Vegetable Tempura

Instructions

1. Prepare the vegetables
   Wash all vegetables thoroughly. Cut sweet potato, eggplant, bell pepper, and zucchini into even slices. Remove stems from shiitake mushrooms. Trim tough ends from asparagus. Pat all vegetables dry with paper towels as excess moisture will prevent the batter from adhering.
2. Make the tempura batter
   In a large bowl, lightly beat the cold egg. Add the ice-cold water and mix briefly. Sift the flour and cornstarch over the liquid and mix very gently with chopsticks or a fork. Leave the batter slightly lumpy - overmixing will develop gluten and make the coating heavy. The batter should be thin and runny.
3. Heat the oil
   Pour 2 inches of vegetable oil into a deep, heavy pot or wok. Heat to 340-350°F (170-180°C). Use a cooking thermometer to maintain the correct temperature throughout the frying process. Too hot and the batter will burn before vegetables cook; too cool and the tempura will absorb oil and become greasy.
4. Fry the vegetables
   Working in small batches, dip vegetables into the batter, allowing excess to drip off. Carefully lower into the hot oil. Fry for 1-2 minutes per side until the batter is light golden and crisp. Avoid overcrowding the pot, which would lower the oil temperature. Sweet potatoes will take slightly longer than other vegetables.
5. Drain and serve
   Remove fried vegetables with a slotted spoon or spider strainer. Place on a wire rack lined with paper towels to drain excess oil. Keep warm in a low oven (200°F/95°C) while frying remaining batches. Serve immediately for maximum crispness.
6. Prepare dipping sauce
   In a small saucepan, combine dashi or vegetable broth, soy sauce, and mirin. Bring to a simmer over medium heat. Remove from heat and let cool slightly before transferring to small individual dipping bowls.