Add the potatoes to a large pot with enough water to fully cover, and add the salt. Bring to a boil, then simmer, covered, for about 15 minutes, or until a fork can easily pierce them.
800 grams waxy potatoes, Water to cover, ~1 tablespoon sea salt
Drain the potatoes, then let them dry in the hot pot, uncovered, for about five minutes. This will ensure that no cooking water is leftover.
Add the vinegar and mustard to the hot potatoes and stir to combine. Set aside to cool fully (transferring to a bowl can help for faster cooling).
2 tablespoons apple cider vinegar, 1 teaspoon Dijon mustard
Once the potatoes have cooled, add the radishes, eggs, green onion, chive flowers, and mayonnaise. Mix to combine, then season to taste with salt and pepper.
1 bunch radishes, 4 hard-boiled eggs, 1 bunch green onion, 1 handful chive flowers or chives, 2 tablespoons mayonnaise, Sea salt and black pepper to taste
Serve at room temperature or refrigerate in a sealed container for up to three days.