With a vegetable peeler, peel a thin strip of yellow lemon zest off the outside of the lemon. You want a thin piece about 1 inch long and 1/2 inch wide. Chop this very finely. Set aside. Juice the lemon. Also set this aside.

Cut a 2 inch section out of the center of one of the cucumbers and cut it into small pieces, about the size of a pencil eraser. Set aside.

Peel the rest of the cucumber, cut it into rough pieces and place in a blender, along with the melon cubes, sweetener, lemon juice and a dash of salt. Puree until smooth.

In a small mixing bowl, mix the yoghurt with the lemon zest, cucumber dice and half of the mint slices.

Pour the soup into 6 bowls, garnishing each bowl with a nice dollop of cucumber yoghurt and finally, dust with the remaining mint slices. Serve!