Miso Soup

Miso Soup is a daily ritual for 75% of Japanese households, combining fermented soybean paste with dashi broth, tofu, and wakame seaweed. With only 40 calories per bowl and 2 grams of protein, it's the lightest item on this list by a wide margin. Miso production dates back to the 7th century, and the paste's salt content ranges from 5% to 15% by region, making this soup cheaper than the typical rival—at about 30 yen per serving, it undercuts #8 Okonomiyaki's cost by 80%.