Tuna Empanaditas

Preparation Preheat oven to 400°F. Pour oil from tuna into a medium skillet. Add onion to skillet and cook over moderate heat, stirring occasionally, until softened, 3 to 4 minutes. Mash tuna in a bowl with a fork, then stir in onion, olives, and capers. Season generously with pepper and very lightly with salt. Roll out 1 pastry sheet on a lightly floured surface with a lightly floured rolling pin into a 13-inch square. Cut out 30 rounds with floured cookie cutter and discard trimmings. Put 1/2 teaspoon tuna mixture in center of each round. Hold 1 filled round in palm of your hand, then moisten edge with a finger dipped in water. Cup hand, then fold dough over to form a half-moon, pinching edges to seal (this creates a border for crimping). Transfer empanadita to an ungreased large baking sheet and press back of a fork onto border to crimp. Form more empanaditas with remaining rounds, then bake on sheet in middle of oven until golden, 20 to 25 minutes. Meanwhile, make more empanaditas with remaining pastry sheet and filling. Bake in same manner. Cool empanaditas on baking sheet on a rack about 10 minutes. Serve warm. Cooks' note:Empanaditas can be formed (but not baked) 1 week ahead. Freeze in 1 layer in a shallow baking pan, then transfer to sealed plastic bags and keep frozen. Bake frozen empanaditas about 30 minutes.

Preparation Preheat oven to 400°F. Pour oil from tuna into a medium skillet. Add onion to skillet and cook over moderate heat, stirring occasionally, until softened, 3 to 4 minutes. Mash tuna in a bowl with a fork, then stir in onion, olives, and capers. Season generously with pepper and very lightly with salt. Roll out 1 pastry sheet on a lightly floured surface with a lightly floured rolling pin into a 13-inch square. Cut out 30 rounds with floured cookie cutter and discard trimmings. Put 1/2 teaspoon tuna mixture in center of each round. Hold 1 filled round in palm of your hand, then moisten edge with a finger dipped in water. Cup hand, then fold dough over to form a half-moon, pinching edges to seal (this creates a border for crimping). Transfer empanadita to an ungreased large baking sheet and press back of a fork onto border to crimp. Form more empanaditas with remaining rounds, then bake on sheet in middle of oven until golden, 20 to 25 minutes. Meanwhile, make more empanaditas with remaining pastry sheet and filling. Bake in same manner. Cool empanaditas on baking sheet on a rack about 10 minutes. Serve warm. Cooks' note:Empanaditas can be formed (but not baked) 1 week ahead. Freeze in 1 layer in a shallow baking pan, then transfer to sealed plastic bags and keep frozen. Bake frozen empanaditas about 30 minutes.