SHRIMP CAKES WITH WASABI VINAIGRETTE

Steps:

• Make dashi:
• Wipe any sand or salt from kombu with a dampened cloth.
• Bring water and kombu almost to a boil in a 2-quart saucepan, then reduce heat and simmer, uncovered, 5 minutes. Add katsuo bushi and bring to a boil, then boil 30 seconds. Remove from heat and let stand 3 minutes, skimming any foam. Pour dashi through a cheesecloth-lined sieve into a bowl.
• Make shrimp mixture:
• Cook carrot, onion, and mushrooms in 1/4 cup dashi, uncovered, in a small heavy skillet over moderate heat, stirring frequently, until carrot and onion are softened, about 4 minutes. Cool slightly.
• Stir together shrimp, fish, vegetable mixture, yolk, sea salt, shoyu, and sugar in a bowl until combined well, then knead with your hands to form a paste. Chill, covered, until cold, about 1 hour.
• Make wasabi vinaigrette:
• Whisk together wasabi paste and mayonnaise, then add mirin and rice vinegar in a slow stream, whisking until blended well. Season with white pepper.
• Make mirin sauce:
• Bring mirin, shoyu, sugar, and 1/4 cup dashi to a simmer in a small saucepan. Stir cornstarch mixture, then whisk into mirin mixture and boil, whisking, 1 minute. Remove from heat and keep warm, covered.
• Fry shrimp cakes:
• Heat oil in a deep 10-inch skillet over moderate heat until it registers 250°F on thermometer. While oil is heating, form shrimp mixture into 4 (1/2-inch-thick) cakes. Fry cakes until light golden, about 2 minutes on each side, then transfer with a wide metal spatula to paper towels to drain. Transfer cakes with spatula to clean paper towels to drain again. Cut each cake into 1/2-inch-wide slices.
• Assemble dishes:
• Divide mesclun among 4 plates and sprinkle with shiso leaves. Arrange shrimp cake slices over salads and drizzle with vinaigrette and mirin sauce. Top each serving with 2 rounded tablespoons katsuo bushi, then with sprouts.