This is a delicious pared-down version of Japanese hiyashi chuka, or cold ramen noodles with various toppings. This recipe calls for seasoned rice vinegar, which is flavored with sugar and salt; it’s a three-in-one ingredient and a simple way to make a well-seasoned dressing. When shopping, look for non-instant dried ramen, sometimes called chukamen or chuka soba; the noodles may be either straight or curly. Additional options for topping the salad include shredded carrots, slivers of tomato and shredded lettuce.