Preheat the oven to 200°C (390°F).

Boil the potatoes until they're soft but not overly done — about 15–20 minutes. Drain and let them sit for 10 minutes to allow most of the moisture to evaporate.

Place the potatoes on a parchment-lined baking tray and gently smash them with the bottom of a glass.

Drizzle with olive oil, then season with salt and pepper. Bake for 30 minutes, or until golden and crispy.

Meanwhile, finely chop the cucumber, red onion, dill, and chives. In a bowl, combine the Greek yoghurt, mayonnaise, vinegar, lemon juice, chili flakes and mustard. Whisk until smooth and well combined. Season with salt and pepper.

Once the potatoes are done, let them cool slightly, then gently fold them into the dressing along with the chopped vegetables and herbs.