Spread wholemeal bread with mustard. Peel onion and cut into fine rings. Wash and clean the bell peppers, cut them into rings and place them on the slice. Wash parsley, pluck off leaves and put 2 leaves on the slice.
Spread the sauerkraut, except for 1 teaspoon, on the bread and place the ham on top. Sprinkle onion rings and the rest of the sauerkraut on top and garnish with parsley.