6 oz dried apricots (1 cup; preferably California)
1/2 cup walnuts (2 ounces), finely chopped
Pierogi and vareniki dough
1 stick (1/2 cup) unsalted butter
1/2 cup fresh bread crumbs
1/4 teaspoon cinnamon
Directions
Bring water and 1/4 cup sugar to a boil, stirring until sugar is dissolved. Remove from heat and stir in brandy. Finely chop apricots in a food processor, then add sugar syrup and pulse until just combined (do not purée). Transfer to a bowl and stir in 1/4 cup walnuts. Cool.
Halve dough and roll out 1 piece on a lightly floured surface into a 15-inch round, keeping remaining dough wrapped. Trim dough to a 13-inch square. Cut lengthwise into 4 strips, then crosswise into fourths to form 16 (3 1/4-inch) squares.
Put 1 slightly rounded teaspoon filling in center of each square. Working with 1 square at a time, moisten edges with water and fold in half diagonally to form a triangle, pressing edges firmly together to seal. overlap bottom points of triangle and press to seal (dumpling will look like a pointed hat). Transfer vareniki to a flour-dusted kitchen towel. Repeat with remaining squares, then make more dumplings with remaining dough and filling.
Cook varenikis in a large pot of lightly salted boiling water until tender, about 15 minutes. Make topping while varenikis cook:
Heat 2 tablespoons butter in a skillet over moderate heat, then cook bread crumbs and remaining 1/4 cup walnuts, stirring frequently, until golden, 2 to 3 minutes. Remove from heat and season lightly with salt. Stir together cinnamon and remaining 2 tablespoons sugar. Sprinkle 2 teaspoons cinnamon sugar over crumb mixture and toss.
Melt remaining 6 tablespoons butter, then drizzle about 2 tablespoons on a warmed serving platter. Transfer varenikis with a slotted spoon to platter and drizzle with remaining 4 tablespoons butter.
Serve hot, sprinkled with bread-crumb mixture and remaining cinnamon sugar to taste.
