Wash the potatoes in boiling water and cook for about 20 minutes. In the meantime wash and clean the zucchini and cut them into quarters lengthwise. Cut the quarters into pieces. Wash and clean the peppers and cut them into slices.
Drain the chickpeas in a sieve. Wash the parsley and dab dry. Pluck off the leaves and chop them coarsely, except for a little to garnish. Drain potatoes, rinse with cold water, peel and dice.
Peel and finely dice the onion and garlic. Mix yoghurt, 3 tbsp. oil, lemon juice and zest, onion and half the garlic. Season with salt, pepper and sugar. Flavour with cumin. Heat 2 tablespoons of oil in a large frying pan.
Fry the zucchini and peppers for about 4 minutes, turning them over. About 1 minute before the end of the cooking time add the remaining garlic and season with salt and pepper. Mix potatoes, zucchini, bell peppers, chick peas and parsley.
Stir the dressing into the salad. Garnish with parsley. Crumbled feta cheese tastes good with it.