In a large bowl, whisk together the flour, cornstarch (¼ cups), and baking soda (½ tsp).

Gradually add the ice water (1 cup) to the dry ingredients, whisking gently until just combined. Do not overmix; a few lumps are okay.

Overmixing develops gluten, leading to a tough batter. • Batter should be thin and slightly lumpy.

Place the bowl of batter in an ice bath to keep it cold.

Maintaining a cold batter is crucial for achieving a crispy texture.

In a large, heavy-bottomed pot or deep fryer, heat the vegetable oil (4 cups) to 350°F (175°C).

Use a thermometer to ensure accurate oil temperature. • Oil should shimmer but not smoke.

Dip the shrimp and vegetables into the cold batter, ensuring they are lightly coated.

Carefully lower the battered shrimp and vegetables into the hot oil, working in batches to avoid overcrowding the pot.

Maintain the oil temperature between batches. • Tempura should be golden brown and crispy. • Listen for a lively sizzle as the tempura fries.

Fry for 2-3 minutes, or until golden brown and crispy. Remove with a slotted spoon and place on a wire rack to drain excess oil.

Serve immediately with your favorite dipping sauce.