1 medium Granny Smith apple, unpeeled, quartered and cored
2 large eggs
2 scallions, green part only, finely chopped
3/4 teaspoon kosher salt
1/2 teaspoon ground black pepper
1/2 cup all-purpose flour
Canola oil (for frying)
4 ounces sour cream
2 Tablespoons chopped red onion
4 ounces thinly sliced smoked salmon
1 Tablespoon chopped fresh chives
Using a food processor fitted with a coarse shredding disc, grate the potatoes, onion and apple at the same time. Transfer the mixture to a colander set in the sink and lined with a lint free kitchen towel. Gather the towel tightly around the potato mixture and squeeze out as much liquid as possible.
Place the potato mixture, eggs, scallions, salt and black pepper in a bowl; toss to blend. Mix in the flour.
Preheat the oven to 300 degrees.
Heat a large sauté pan over medium-high heat. Pour enough canola oil into the bottom of
the pan to cover the bottom. Working in batches, drop heaping Tablespoons of the potato mixture into the skillet for each pancake. Flatten each mound with the spoon to form a 2- inch round cake. Fry until cooked through and crisp, about 2 minutes per side.
Transfer the potato cakes to a baking sheet and keep warm in the preheated oven while you continue with the remaining potato mixture.
Garnish the pancakes with the smoked salmon and a dollop of the sour cream. Sprinkle with red onion and chives and serve.