Perfectly stacked layers of dark chocolate cake and ganache over buttercream, with just a touch of orange extract, make this cake a true showstopper. This is a dessert that you’ll want to show off before it’s all eaten-up.
Preheat oven to 350°F. Prepare cake pan with vegetable pan spray.
In large bowl, prepare cake mix as directed on box. Mix in instant coffee and 1 1/2 teaspoons extract with electric mixer on low speed 30 seconds. Scrape bottom and sides of bowl; beat on medium speed 2 minutes. Divide batter evenly between pans.
Bake 16-18 minutes or until toothpick inserted in center comes out clean. Cool cakes in pans on cooling rack 10 minutes. Remove from pans; cool completely on grid. Once cooled, cut each cake horizontally into two layers, creating four even layers of cake.
For ganache, combine cream and chocolate in medium microwave-safe container. Microwave at half (50%) power 1 minute; stir. Microwave on 50% power in 15-second intervals, stirring between each, until chocolate is almost melted. Add 1/4 teaspoon orange extract and stir thoroughly until ganache is smooth.
For icing, beat butter and shortening in large bowl with electric mixer until light and fluffy. Add melted chocolate; beat until combined. Add confectioners’ sugar, 1 cup at a time, beating well on medium speed. Scrape sides and bottom of bowl often. Add milk, 1 tablespoon at a time, and beat on medium speed until light and fluffy.
To assemble, spread 1/4 of buttercream on first cake layer. Spread 1/4 of ganache over buttercream. Repeat with remaining layers, leaving sides of cake bare.