In a large pot, bring water to a boil over high heat. Now reduce heat to maintain a gentle simmer. Break up nori into 3-4 pieces and add to water. Simmer for 1-2 minutes until it breaks down.
Remove from heat and pour broth through a Mesh Strainer into another pot or large heat-safe bowl. Return strained broth to the pot and return to the stovetop over medium heat. Discard nori.
Add tofu and green onions. Bring to a gentle simmer for 1-2 minutes to warm tofu throughout. Remove from heat.
Place a mesh strainer over the pot and add the miso paste. Dissolve using a spoon or spatula (see note for alternative method). Serve and enjoy!
SOY-FREE OPTION: Instead of soy-based miso paste, you can use Chickpea Miso. You can replace the tofu with chickpeas, sautéd mushrooms, or fresh-chopped spinach. SEAWEED: You can use any seaweed to make the broth. If you don't like the taste of seaweed, you can omit that step altogether. Instead, you can substitute ½ the water with vegetable broth. Alternative method to dissolve miso paste: add paste to a medium bowl with about ½-1 cup of prepared broth. Whisk well to combine and then add the soup. If you want to amp up the umami flavor, you can add a few splashes of low-sodium tamari or vegan fish sauce.