Preheat oven to 350 degrees F.

Melt chocolates and butter over a double boiler, stir until smooth and remove from heat. In a large bowl, sift together flour, cocoa powder, baking powder, salt and espresso. Set aside. In a mixing bowl, beat sugar, egg and vanilla on medium high until light colored about 2 minutes. Beat in chocolate until well combined. Add flour mixture slowly until well blended. Stir in hazelnuts.

Pour mixture into a 11 x 7 - inch non stick baking pan and bake for 35-40 minutes or until toothpick inserted 2 inches from the side comes out clean. Cool completely. Cut into 8 rectangles.

Photo and Recipe Courtesy of Whole Foods Market.