Cook the potatoes in boiling water for about 20 minutes. Wash fish, remove existing bones. Peel and finely dice onion. Heat 1 tbsp. butter in a pan and fry the onion for about 5 minutes until transparent.
Douse with white wine. Add the fish and cook in the closed pan for about 5 minutes.
Wash the parsley, dab dry, remove the leaves except for a little to garnish, pluck from the stalks and chop finely. Drain potatoes, rinse, peel and press through a potato ricer. Prepared ingredients, except for some parsley for sprinkling, crabs, except for some for sprinkling, 1 egg, flour and breadcrumbs loosely mix.
Season with salt and pepper and form into 8 meatballs.
Heat 4 tablespoons of butter in a large pan and fry the meatballs for about 6 minutes, turning them over. In the meantime whisk the remaining eggs and season with salt and pepper. Heat 2 tbsp. butter in a frying pan and stir-fry the eggs for approx. 4 minutes.
Spread the scrambled eggs on slices of bread. Arrange slices of bread and meatballs on plates. Sprinkle with parsley, crabs and caviar. Garnish with parsley.