Ingredients
Horseradish sour cream:
1/2 cup mashed potatoes (optional)
1/2 cup sour cream
1 tablespoon finely grated peeled fresh horseradish
1 teaspoon chopped fresh dill
1 teaspoon chopped fresh flat-leaf parsley
1 teaspoon fresh lemon juice
Kosher salt, ground pepper
Assembly:
4 slices Danish rye or pumpernickel bread
8 ounces sliced smoked salmon
2 radishes, thinly sliced
2 tablespoons salmon or trout roe (optional)
Dill sprigs and flat-leaf parsley leaves
Kosher salt, ground pepper
Preparation
For horseradish sour cream: Whisk potatoes, if using, sour cream, horseradish, dill, parsley, and lemon juice in a small bowl; season with salt and pepper. For assembly: Spread horseradish sour cream on bread and top with smoked salmon, radishes, roe, if using, dill, and parsley. Season with pepper.
