For the tzatziki, peel the onion and garlic and cut into fine cubes. Wash and clean the cucumber, cut off 16 thin slices and grate the remaining cucumber. Mix yoghurt, cucumber, onion and garlic.
Season to taste with salt, pepper and lemon juice. Heat the oil in a pan and fry the sausages for about 10 minutes while turning them until crispy. Cut 4 sausages in half. Arrange 1 1/2 sausages each with tzatziki and bread on plates.
Dust with curry and garnish with cucumber and parsley.