Wash and clean the zucchini and cut them into pieces. Peel and chop the onions. Clean, wash and roughly chop the peppers. Put everything in a pot and mash it briefly with a hand blender.
Stir in jam sugar, mustard powder, vinegar and apple juice. Season with salt, pepper and nutmeg. Boil up while stirring. Simmer for about 15 minutes, stirring several times.
Wash parsley, shake dry and chop finely. Stir the parsley into the relish and continue cooking for about 1 minute. Season to taste with salt and pepper. Pour hot into prepared clean glasses and close them well. Store in a cool and dark place.