1. Slice the cucumbers into long, even and very thin strips using a mandoline. Top the strips with salt, leave them for a few minutes to draw the moisture out, then dry with paper towel.
2. In the meantime, drain the tuna and break it into pieces.
3. Spread a little yoghurt and a piece of tuna on top of each cucumber strip, wrap to create a small roll and secure with a toothpick.
4. Arrange the rolls on a plate and top with some pepper and a drizzle of oil.
