Crispy Tempura

1. In a mixing bowl, combine flour, cornstarch, baking powder, and salt. 2. In a separate bowl, whisk together egg and ice water. 3. Gradually add the wet mixture to the dry ingredients and stir until just combined. Do not overmix, a few lumps are okay. 4. Heat oil in a deep fryer or a large pot to 375°F (190°C). 5. Dip vegetables or seafood in the batter, making sure they are fully coated. 6. Fry in batches until golden and crispy, about 2-3 minutes. 7. Remove tempura with a slotted spoon and place on a paper towel-lined plate to drain excess oil. 8. Serve hot with dipping sauce.