Whisk the dressing first: In a small bowl, whisk the vinegar, sugar, and salt until the sugar has completely dissolved. Then whisk in the oil and half of your chives.
Toss: Pour the dressing over the 200g of vegetables and toss thoroughly.
Wait: Let it sit for at least 15 minutes. This 'macerates' the vegetables, making them slightly more tender while keeping their crunch.
Final Touch: Just before serving, sprinkle the remaining fresh chives on top for a pop of bright green.