Hiyashi Chuka (Cold Ramen Salad)

Mix together the soy sauce, vinegar, mirin, water, ginger, and sesame oil in a small bowl and set aside in the refrigerator to chill.

Bring a large pot of water to a rapid boil. Add the ramen noodles, separating them as you carefully lower them into the water. Cook, stirring often, until just al dente, about 2 minutes. Drain the noodles in a strainer, rinsing them under cold water to stop the cooking process. Put the strainer of noodles on a plate in the refrigerator to drain well and chill.

If including egg: In a small bowl, beat 1 egg with a fork. Pour the egg into a nonstick skillet (it should have a lid) and cook over medium-low heat, swirling it around so that it’s a thin even layer. When the bottom is cooked, about 2 minutes, cover the pan with the lid. Cook until the top of the egg is set about 1 minute. Use a rubber spatula to roll the sheet of egg like an omelet and remove it from the pan. Cut the rolled omelet into thin (1/8-inch) strips. Repeat with the other egg. Set aside.

Prepare your vegetables: Cut the kernels from the corn cob and set aside. (For baby corn, leave them whole.) Cut the scallions on a diagonal into very thin slices and set aside. Julienne the carrots and cucumbers into fine matchstick pieces, with a knife or mandoline, and set aside. Cut the tomato into 6 wedges and set aside. Cut the avocado into slices.

Mound half of the ramen noodles in the center of a plate. Arrange half of each of the vegetables — corn, carrots, scallions, cucumbers, tomato, and avocado — and the sliced omelet on top of the noodles. Put half of the radish sprouts on top as garnish and sprinkle with sesame seeds. Repeat for a second plate. Put a little spicy mustard on the edge of each plate. Serve immediately, with the dressing alongside.