Step 1In a bowl, mix the jalapeno, ginger, green onions, soy sauce, lime juice, lemon juice, vinegar and dashi. Steep for at least several hours or up to two days. Strain and refrigerate until ready to use. Makes 1 1/4 cups.
Step 1In a small skillet, combine the sake, mirin, soy sauce, garlic, green onion and ginger. Cook over medium heat until reduced to one-half cup, about 30 minutes. Strain and cool.
Step 1Heat a grill or grill pan. Place the fillets on the grill and cook 4 minutes. Turn the fish over and brush with some of the mirin reduction sauce. Cook until they just start to feel firm to the touch, about 3 to 4 minutes.
Step 2Drain the cucumber strips and pat them dry. Place them in a bowl and stir in 2 tablespoons ponzu sauce.
Step 3Spoon 2 tablespoons ponzu sauce onto each of 4 plates. Place the cucumbers, avocado slices, romaine, pickled ginger and sprouts clockwise around the plate so they touch in the middle of the plate.
Step 4Put the shiso leaf in the middle of each plate where the ingredients meet. Place a fillet on the leaf, allowing the edge of the leaf to show. Drizzle the remaining ponzu sauce over the fish and salad ingredients, sprinkle with the sesame seeds and serve.