Place liqueur in a small bowl. Microwave at HIGH 10 seconds. Stir in cocoa and espresso until smooth.
Add oil, egg whites, and egg, stirring with a whisk until blended.
Lightly spoon flours into dry measuring cups; level with a knife.
Place flours, sugars, 2 tablespoons hazelnuts, baking soda, and salt in a food processor; process until nuts are ground.
Add ground coffee; pulse 2 times or until blended. With processor on, slowly add liqueur mixture through food chute; process until dough forms a ball.
Add remaining 6 tablespoons hazelnuts; pulse 5 times or until blended (dough will be sticky). Turn dough out onto a floured surface, and knead lightly 4 or 5 times. Divide into 3 equal portions, shaping each portion into a 10-inch-long roll.
Place rolls 3 inches apart on a large baking sheet coated with cooking spray.
Bake at 300 for 28 minutes.
Remove rolls from pan; cool 10 minutes on a wire rack.
Cut each roll diagonally into 20 (1/2-inch) slices.
Place slices, cut sides down, on baking sheets.
Bake at 300 for 20 minutes. Turn cookies over; bake an additional 10 minutes (cookies will be soft in center but will harden as they cool).
Remove cookies from pans; cool completely on wire racks.
