Place hazelnuts in an ungreased 15" x 10" x 1" jellyroll pan. Toast at 350° for 12 minutes or until skins begin to split. Transfer hot nuts to a colander; cover with a kitchen towel. Rub nuts briskly with towel to remove skins. Let nuts cool, and chop.
Grease and flour two 9" cakepans. Prepare cake mix according to package directions; pour into prepared pans. Bake at 350° for 30 minutes or until a wooden pick inserted in center comes out clean. Let cool in pans on wire racks 15 minutes; remove from pans, and let cool completely on wire racks.
Prepare mousse mix according to package directions, using 1 1/3 cups milk; cover and chill.
Split cake layers in half horizontally to make 4 layers. Place 1 layer on a serving plate lined with wax paper. Spread one-third of mousse over layer. Repeat procedure with second and third layers and remaining mousse. Top stack with fourth layer. Chill 30 minutes.
Combine whipping cream and coffee powder in a saucepan; bring to a simmer over medium heat. Remove from heat; add chocolate. Let stand 1 minute. Stir until chocolate melts. Cool 30 minutes.
Pour chocolate glaze over torte, letting excess drip down sides onto wax paper. Using a small spatula, smooth excess glaze onto sides of torte. Gently press hazelnuts onto sides of glazed torte. Carefully pull wax paper from beneath torte. Store in refrigerator.
Note: We used Duncan Hines devil's food cake mix, Nestle mocha mousse mixes, and General Foods International Coffees Suisse Mocha.