Peel and chop the onion and garlic. Clean, wash, quarter and cut the pointed cabbage into strips. Clean, wash and chop the bell peppers. Wash rosemary, shake dry, remove needles and chop finely.
Heat the oil in a pot and fry the prepared vegetables briefly. Deglaze with broth and simmer covered for about 10 minutes.
Cut the bacon into pieces. Distribute on a baking tray lined with baking paper. Bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for 8-10 minutes until crispy.
For the Gremolata, wash the herbs and shake dry. Pluck off leaves and chop finely. Mix with lemon peel. Chop tomatoes coarsely and add to the soup with the juice. Bring everything to the boil again.
Season to taste with salt, pepper and sugar. Serve soup sprinkled with gremolata and ham chips.