Prepare the tentsuyu dipping sauce by combining dashi stock, soy sauce, and mirin in a small saucepan. Heat over medium heat until just simmering, then remove from heat and set aside to cool slightly.

Pat shrimp completely dry with paper towels. Make 3-4 shallow cuts on the underside of each shrimp to prevent curling during frying.

Cut asparagus spears in half if longer than 12cm. Pat dry thoroughly with paper towels.

In a large bowl, combine 150g flour and cornstarch. In a separate bowl, whisk together egg yolk and ice-cold sparkling water.

Pour wet ingredients into dry ingredients and stir briefly with chopsticks, leaving the batter slightly lumpy for extra crispiness. Do not overmix.

Heat vegetable oil in a deep pot or wok to 170-180°C. Use a thermometer to monitor temperature throughout frying.

Lightly dust shrimp and asparagus in flour, shaking off excess. Dip into batter, allowing excess to drip off.

Fry asparagus pieces for 2-3 minutes until light golden and crispy. Remove and drain on a wire rack.

Fry shrimp in batches for 3-4 minutes, turning once, until golden and cooked through to an internal temperature of 75°C. Drain on wire rack.

Serve immediately on a paper-lined plate with tentsuyu dipping sauce, garnished with grated daikon and fresh ginger on the side.