Trim off the ends and peel the thick outer skin from your kohlrabi. Shred or cut into matchsticks. A julienne peeler makes quick work.
Remove the ends of the radishes and then slice them thinly, and do the same for the onions.
Place kohlrabi, radishes and onions in a bowl and add lemon or lime juice, vinegar, sunflower/olive oil, sugar and a pinch of sea salt.
Refrigerate for 15 minutes. Taste to adjust seasoning, stir in herbs, and serve.