Add all the dressing ingredients to a small mixing bowl and stir well to combine.
Lay the cucumber slices across a clean work surface. Divide the dressing mixture evenly between the strips, spreading a generous layer across the length of each strip.
Sprinkle the chopped mint across the cucumber slices.
Divide the chopped tomatoes, olives and onion between the strips, starting at one end of the cucumber and covering 1/3 of the length.
Carefully roll from the filled end of the cucumber, wrapping the filling tightly in the centre until to have a neat roll. Refrigerate until ready to serve.