Crab Wrapped in Wakame Seaweed

For sauce, combine niban-dashi, rice vinegar, mirin, and soy sauce in a bowl. Grate ginger, then place it in a clean dish towel and squeeze to yield about 1 tsp. ginger juice. Stir juice into dashi mixture.

Blanch seaweed in a pot of boiling water over high heat for 30 seconds, then plunge it into a bowl of ice water. Drain and pat dry. Cut tough vein at top and all loose, long fronds away from each piece of wakame, leaving 1 rectangle. Overlap 3-4 of these pieces on a bamboo sushi rolling mat, making a 6 1⁄2'' x 4'' sheet of wakame.

Pick bits of shell from crab meat, then spread half of the crabmeat along long edge of wakame nearest you. Pressing firmly, roll mat, shaping wakame and crab into one long roll. Trim edges, then cut roll into 6 pieces. Repeat process with remaining wakame and crab.

Place 3 pieces of wakame-wrapped crab on each plate; spoon sauce on top. Finely grate enough peeled daikon to make about 1⁄2 cup. Squeeze excess juice from daikon; mound about 1 tbsp. daikon on each plate. Garnish with fresh mitsuba (trefoil) and 1 tsp. salmon roe.