Peel and chop the onions and garlic. Clean, wash and cut the zucchini into large pieces.
Heat the oil in a large pot. Brown the onions and garlic in it. Fry the zucchini briefly. Deglaze with 800 ml water, bring to the boil and stir in broth. Cover and simmer over low heat for 5-8 minutes.
Whip the cream until semi-stiff. Puree the soup with a hand blender. Stir in half the cream and season with salt, pepper and 1 pinch of sugar. Crumble the gorgonzola roughly. Serve the soup with the remaining cream and gorgonzola.
Sprinkle with coarse pepper.