For the tartar sauce, finely chop half the cucumber salad. Peel the mango, cut it from the stone and crush it finely with a fork. Mix yoghurt, mayonnaise, mango, 1 tsp lemon juice, Sambal Oelek and 1 1⁄2 tsp curry.
Stir in chopped cucumbers. Season with salt and 1 pinch of sugar.
For the salad drain the corn. Clean and wash spring onions and cut into fine rings. Halve the avocado, remove the core, remove the flesh from the skin and dice finely. Mix the corn, spring onions, avocado, rest of cucumber salad and 2 tbsp. lemon juice.
Season to taste with salt and chili flakes.
Score the sausages at an angle at a distance of approx. 1 1⁄2 cm. Heat the oil in a large pan and fry the sausages for about 8 minutes. In the meantime peel and roughly dice the onion. Mix with the fried onions.
Cut the buns lengthwise so that they still stick together at the bottom. Spread a part of tartar sauce evenly on the rolls. Put 1 sausage in each roll. Spread the salad evenly on the rolls. Add the rest of the tartar sauce and serve sprinkled with onion mix.