PreparationFor coffee syrup: Combine all ingredients in small saucepan. Stir over low heat until sugar and coffee dissolve. Let cool. (Can be made 2 days ahead. Chill.) For cake: Position rack in center of oven; preheat to 350°F. Butter two 9-inch-diameter cake pans with 2-inch-high sides. Line bottoms with waxed paper; butter paper. Dust with flour. Stir chocolate in top of double boiler set over simmering water until melted. Remove from over water. Sift flour, baking powder, cinnamon and salt into medium bowl. Stir coffee powder into milk in another medium bowl until dissolved. Using electric mixer, beat sugar and butter in large bowl until well blended. Beat in eggs 1 at a time. Mix in melted chocolate and vanilla. Add dry ingredients alternately with milk mixture in 3 additions. Divide batter between pans. Bake cakes until tester inserted into center comes out clean, about 35 minutes. Cool cakes in pans on racks 10 minutes. Cut around pan sides. Turn cakes out onto racks and cool completely. Peel off paper. Cut each cake horizontally in half. Using bottom of tart pan as aid, transfer 1 cake layer, cut side up, to platter. Brush cake layer with 2 tablespoons syrup. Spread 3/4 cup frosting over cake layer. Repeat layering 2 times, using 1 cake layer, 2 tablespoons syrup and 3/4 cup frosting for each layer. Top with fourth cake layer, cut side down. Spread remaining frosting over cake. (Can be made 1 day ahead. Cover and let stand at room temperature.)
PreparationFor coffee syrup: Combine all ingredients in small saucepan. Stir over low heat until sugar and coffee dissolve. Let cool. (Can be made 2 days ahead. Chill.) For cake: Position rack in center of oven; preheat to 350°F. Butter two 9-inch-diameter cake pans with 2-inch-high sides. Line bottoms with waxed paper; butter paper. Dust with flour. Stir chocolate in top of double boiler set over simmering water until melted. Remove from over water. Sift flour, baking powder, cinnamon and salt into medium bowl. Stir coffee powder into milk in another medium bowl until dissolved. Using electric mixer, beat sugar and butter in large bowl until well blended. Beat in eggs 1 at a time. Mix in melted chocolate and vanilla. Add dry ingredients alternately with milk mixture in 3 additions. Divide batter between pans. Bake cakes until tester inserted into center comes out clean, about 35 minutes. Cool cakes in pans on racks 10 minutes. Cut around pan sides. Turn cakes out onto racks and cool completely. Peel off paper. Cut each cake horizontally in half. Using bottom of tart pan as aid, transfer 1 cake layer, cut side up, to platter. Brush cake layer with 2 tablespoons syrup. Spread 3/4 cup frosting over cake layer. Repeat layering 2 times, using 1 cake layer, 2 tablespoons syrup and 3/4 cup frosting for each layer. Top with fourth cake layer, cut side down. Spread remaining frosting over cake. (Can be made 1 day ahead. Cover and let stand at room temperature.)