Set a rack in the middle of the oven and preheat to 350 F. Lightly grease a 12-inch by 18-inch cookie sheet to anchor the paper and line it with parchment paper. Lightly grease the paper.
Put the flour, cocoa, and sugar in a large bowl and stir together with a whisk.Whisk in the nuts. Gradually whisk in the coffee and Frangelico until smooth.
With an offset metal spatula, spread half of the batter onto the cookie sheet in an even 1/16-inch thick layer. Bake for 15 minutes, or until crisp. Set on a rack to cool. Repeat with the remaining batter. To serve, break the sheets into pieces.