Peel the cucumber and cut them in thin strings. Sprinkle lightly with salt and let it rest. In the meantime, cut the turkey breast in slices, season with pepper and salt and grill in a pan.
Chop the garlic and cut the radishes in fine bars. Squeeze the moisture out of the cucumber and mix with the yoghurt and garlic. Season with pepper and the green lemon juice.
Roast the bread. Make a sandwich with lettuce, turkey and the mix with Greek yoghurt.