Rinse the salmon head, tail, and fins thoroughly, removing any blood or loose fragments. Place them in a medium pot and add 6–8 cups of cold water. Bring slowly to a gentle boil over medium heat. Reduce heat to a steady simmer. Skim off any foam that rises to the surface. Simmer uncovered for 25–35 minutes, allowing the broth to extract flavor, oils, and nutrients.

Remove the head, fins, and tail and place them on a baking sheet. Once cool enough to handle, carefully scrape off all usable meat, including the cheeks. Discard bones and cartilage. Return the picked fish meat to the pot.

Season the broth with sea salt to taste. Stir in the dried black seaweed and simmer for another 5–10 minutes, until the seaweed softens and the broth deepens in color and aroma.

Gently add the salmon eggs near the end of cooking. For soft, delicate eggs, add during the last 3–4 minutes. For firmer eggs, add 5–7 minutes before removing from heat. Avoid vigorous stirring to keep the eggs intact.

Remove soup from heat and let rest briefly. Taste and adjust seasoning as needed. Serve hot.