Wash the cutlets, dab dry and spread with about 1 teaspoon of mustard each. Peel and finely dice the onion. Cut chives into fine rolls. Sprinkle schnitzel with onion and chives. Clean and wash the zucchini and cut them lengthwise into thin slices. Cover the schnitzel, season with salt and pepper and roll up.
Fix with wooden skewers. Heat oil in a pan and fry the rolls in it all around. Deglaze with broth, bring to the boil, cover and stew over a low heat for about 10 minutes. Remove from the pan and allow to cool down if necessary. Garnish with lettuce leaves as desired and serve