Prepare the dashi stock according to package instructions if you’re using instant dashi. Bring it to a gentle simmer in a medium-sized pot.

In a small bowl, mix the miso paste with a little bit of the warm dashi stock to dissolve it. This prevents lumps of miso in your soup.

Add the dissolved miso back into the pot with the rest of the dashi. Stir gently to combine. It’s important not to let the soup boil after adding the miso, as high heat can destroy its delicate flavor.

Add the tofu cubes and nori strips to the soup. If you’re using additional ingredients like vegetables or wakame, add them at this stage.

Heat the soup just until everything is warm, but be careful not to boil it.

Serve the soup in bowls, garnished with sliced green onions.