If you have a canelle knife, use it to remove strips of peel along the entire length of the cucumber to give a striped effect. If you don't have a canelle knife use a vegetable peeler to do the same thing. Slice the cucumber into very thin rounds with a sharp knife.
Put the cucumber rounds into a plastic container, add the salt, sugar, dill, garlic, lemon juice and olive oil and mix together gently. Cover the container and marinate in the refrigerator for 24 hours, stirring occasionally.
Just before serving, drain the cucumber and mix it with the yoghurt. Serve in individual dishes with crusty bread.
• If you don't have dried dill, try dried mint instead. • In the summer, when fresh herbs are plentiful, use finely chopped fresh dill or mint and add to the cucumber with the yoghurt, then use a sprig of the herb as an attractive garnish.