Chocolate Coffee Cream-Filled Cookies Recipe

Preheat oven to 350° and grease 3 or 4 baking sheets.
In a bowl, beat butter and sugar until light and fluffy.
In separate bowl, beat egg with coffee granules until dissolved. Gradually add to creamed mixture, beating well.
Sift the flour, cornstarch and baking powder over mixture.
Stir in to make a soft dough and knead lightly.
On a floured surface, roll dough to a 1/8-inch thickness.
With a 2-inch fluted cutter, cut out cookies and place on prepared baking sheets.
Bake 10-15 minutes, until firm and lightly browned.
Transfer cookies to wire racks to cool.
Put the cooled, melted chocolate into a pastry bag and snip off end.
Pipe parallel zigzag lines on half the cookies.
For cookie filling: In bowl, beat butter and powdered sugar until smooth and creamy.
In another bowl, mix egg yolk with coffee granules; add to creamed mixture and beat until smooth.
Spread the filling on plain cookies and then sandwich together.
Let cool in cool place until filling is firm.