Do not reheat the miso soup after the miso has been added; the flavor diminishes with reheating. Miso paste is generally available in the Asian sections of well-stocked supermarkets, as well as at Asian markets; age tofu (deep-fried tofu) is available at
1 quart dashi
3 to 4 tablespoons miso paste (red or white or koji miso paste), or to taste
2 age tofu
1 to 2 leaves nappa cabbage, sliced crosswise into ½-inch thick strips, or any greens of your choice.
2 green onions, sliced thinly to garnish