This recipe makes 100 of these beautiful chocolate cookies. Make them to give as gifts or to bring to a cookie exchange.
In a medium mixing bowl, stir together the flour, cocoa powder, and baking powder. Set the mixture aside.
In a food processor bowl or blender container, process or blend nuts and 2 tablespoons sugar until nuts are finely ground. Add almond paste and process or blend until mixture forms a paste.
In a large mixing bowl, beat butter and the 2/3 cup sugar with an electric mixer on medium to high speed until fluffy. Add the nut paste and vanilla; beat well. Beat in egg whites until just mixed.
Beat in as much of the flour mixture as you can with the electric mixer; stir in any remaining flour mixture with a wooden spoon. Divide dough in half. Cover and chill for 1 hour or until dough is easy to handle.
Roll half of the dough between sheets or parchment paper or waxed paper to form a 12x10-inch rectangle.
Cut dough into 2-inch squares; cut squares diagonally into triangles. (Or using a 1-1/2- to 2-inch cutter, cut into desired shapes.) Mark with the back of a fork. Place 2 inches apart on an ungreased cookie sheet. Repeat with the remaining dough.
Bake in a 350 degree F oven for about 8 minutes or until edges are set. Cool the cookies on the cookie sheet for 2 minutes. Transfer the cookies to wire racks and cool completely.
In a small saucepan, heat and stir chocolate pieces and shortening over low heat until melted. (If you use both of the kinds of chocolate, melt them separately with 1 teaspoon shortening each.) Drizzle over cookies; let stand until set. Store in airtight containers.