Ingredients :

• Cucumber — The pillar of the salad. Prefer a cucumber that feels firm to the touch — if it yields slightly, it’s already a bit old and will release too much water into the marinade. Cut it into thin slices, not thick: this is what allows the marinade to truly penetrate.
• Tomatoes — No need for fancy varieties. Classic round tomatoes work just fine, provided they are ripe. A mealy, tasteless tomato won’t be saved by the marinade. In winter, cherry tomatoes hold up much better.
• White onion — It brings bite and that light pungency that cuts through the sweetness of the sugar. If you find it too strong raw, soak the slices in cold water for 10 minutes beforehand: it removes the bitterness without killing its character.
• Distilled white vinegar — This is what structures the entire marinade. White vinegar is the most neutral — it acidifies without adding any distracting flavors. Apple cider vinegar also works if you want a slightly fruity note.