Tempura, Pt. 1

Chef Nobu Matsuhisa prepares traditional tempura, with Martha.

Nobu's Tempura

FOR THE SWEET AND SOUR PONZU SAUCE:
- 1/2 cup plus 2 tablespoons rice vinegar
- 1 tablespoon soy sauce
- 1 1/2 teaspoons freshly squeezed lemon juice
- 6 tablespoons sugar
- 2 1/2 teaspoons sea salt
- 3/4-inch square piece konbu
- Vegetable oil, for frying
- All-purpose flour, for dredging
- 3 pounds assorted seafood, such as shrimp (peeled, deveined, and butterflied), Alaskan king crab legs (shells removed), and sea urchin (left whole)
- 1 pound assorted vegetables, such as Japanese eggplant (cut crosswise into bite-size pieces, slice through cut end, not all the way through, every 1/4 inch to make a fan), hearts of palm (sliced 1/4 inch thick), sweet potatoes (sliced 1/4 inch thick), eno
FOR THE TEMPURA BATTER:
- 1 large egg, chilled
- 3/4 cup ice water
- 1 cup plus 2 tablespoons all-purpose or low-gluten flour, chilled
FOR THE TRADITIONAL DIPPING SAUCE:
- 1 cup Nobu's Dashi
- 1/4 cup soy sauce
- 1/4 cup mirin
- Grated daikon, for serving
- Minced ginger, for serving
FOR THE KING CRAB TEMPURA:
- 1/2 red onion, halved, thinly sliced, and kept in cold water
- 1/2 cup fresh cilantro leaves
- 3 jalapenos, thinly sliced crosswise into rounds
FOR THE SEA URCHIN TEMPURA:
- Coarse salt and freshly ground black pepper, for serving
- 2 tablespoons freshly squeezed lemon juice, for serving
- 2 tablespoons shi chi mi (Asian hot pepper seasoning), for serving

Prepare the Sweet & Sour Ponzu Sauce; Stir together all ingredients in a small bowl; let stand overnight. Strain.
In a Dutch-oven, heat 3 1/2 inches of oil to 355 degrees. Place flour in a pie plate; set aside.
Prepare Tempura Batter; Combine egg and iced water in a medium bowl; gradually add flour, whisking gently until just combined. Batter will be lumpy.
Prepare Traditional Dipping Sauce; Combine dashi, soy sauce, and mirin in a small saucepan; heat until just before boiling point. Remove from heat; let cool slightly. Pour into a small serving bowl; add about 1 tablespoon each daikon and ginger.
In small batches, lightly dredge pieces of seafood and vegetables in flour, dip in batter, and using tongs, fry in the hot oil, being careful not to overcrowd the pot, until lightly golden and cooked through. (Leave enoki and shiitake mushroom caps plain, battering just stems.) Transfer to a paper towel-lined baking sheet to drain. Allow oil to reheat between batches. Repeat with remaining ingredients.
Transfer vegetable and shrimp tempura to a serving platter; serve with traditional dipping sauce. Place sea urchin tempura on a small serving plate; serve with salt, pepper, lemon juice, and shi chi mi on the side for dipping. Arrange king crab tempura on a serving platter, and garnish with red onion, cilantro, and jalapeno; pour Sweet & Sour Ponzu Sauce over. Serve immediately.