Soak herring in water
Boil potatoes for 10 minutes, drain, let cool, peel and slice them
Saute ham and onions in 1 tbsp butter until light brown
Preheat oven to 350°F/180°C
Cut liver and herring into strips
Add layer of sliced potatoes into a buttered glass dish
Add a layer of diced ham and onions
Add a layer of herring and veal liver strips
Add a layer of sliced potatoes
Mix egg and sour cream. Pour over bake layers
Top souffle with breadcrumbs
Bake dish in preheated oven for about 30 minutes