Onion And Herring Sandwich - Smorrebrod - cooking recipe

Ingredients

4 teaspoons butter, softened
4 slices danish pumpernickel bread or 4 slices rye bread, crusts removed
1 (8 ounce) jar herring fillets, in wine sauce drained and fillets cut into 1-inch strips
1 medium sweet onion, cut into thin rings
1 tomatoes (8 thin slices)
watercress or parsley sprig, for garnish

Preparation

Spread 1 teaspoon butter on each slice of bread, being sure to cover each completely.
Cut each buttered slice in half crosswise or into 2 (4-by-2-inch) pieces.
Top each piece of bread with one-eighth of the herring, placing the fish smooth-side up.
Top each with several onion rings and 1 tomato wedge.
Garnish with watercress or parsley.