PreparationFor cake: Preheat oven to 350°F. Butter and flour 8-inch square metal cake pan. Line bottom of pan with parchment paper. Butter and flour parchment paper. Stir chopped chocolate in top of double boiler set over simmering water until chocolate is melted and smooth. Remove from over water. Using electric mixer, beat butter in medium bowl until smooth. Gradually add sugar and beat until well blended. Beat in eggs 1 at a time, blending well after each addition. Beat in melted chocolate and vanilla. Add flour and cinnamon; beat just until blended. Spoon cake batter into prepared pan; smooth top. Bake cake until tester inserted into center comes out with moist crumbs attached, about 25 minutes. Cool cake in pan on rack 20 minutes. Run small knife between edge of cake and pan to loosen. Turn cake out onto rack; remove parchment paper. Cool completely. For icing: Stir white chocolate and whipping cream in top of double boiler set over simmering water until melted and smooth. Remove from over water. Stir in peppermint extract. Spread icing evenly over top of cake. Place cake in freezer until icing is firm, about 30 minutes, or refrigerate cake 1 hour. For glaze: Bring cream to simmer in heavy small saucepan. Remove from heat. Add chocolate; whisk until melted and smooth. Cool chocolate until lukewarm but still pourable, about 5 minutes. Place cake on rack set over baking sheet. Pour half of glaze over top of cake. Spread glaze evenly over top and sides of cake. Freeze until glaze is set, about 10 minutes. If necessary, rewarm remaining glaze just until pourable. Pour remaining glaze over cake; spread glaze smoothly over top and sides of cake. Refrigerate cake until glaze is firm, about 2 hours. (Can be made 1 day ahead. Cover and keep chilled.) Let cake stand at room temperature at least 3 hours before serving. Transfer brownie cake to platter. Top cake with chocolate curls and garnish platter with mint sprigs and strawberries, if desired
PreparationFor cake: Preheat oven to 350°F. Butter and flour 8-inch square metal cake pan. Line bottom of pan with parchment paper. Butter and flour parchment paper. Stir chopped chocolate in top of double boiler set over simmering water until chocolate is melted and smooth. Remove from over water. Using electric mixer, beat butter in medium bowl until smooth. Gradually add sugar and beat until well blended. Beat in eggs 1 at a time, blending well after each addition. Beat in melted chocolate and vanilla. Add flour and cinnamon; beat just until blended. Spoon cake batter into prepared pan; smooth top. Bake cake until tester inserted into center comes out with moist crumbs attached, about 25 minutes. Cool cake in pan on rack 20 minutes. Run small knife between edge of cake and pan to loosen. Turn cake out onto rack; remove parchment paper. Cool completely. For icing: Stir white chocolate and whipping cream in top of double boiler set over simmering water until melted and smooth. Remove from over water. Stir in peppermint extract. Spread icing evenly over top of cake. Place cake in freezer until icing is firm, about 30 minutes, or refrigerate cake 1 hour. For glaze: Bring cream to simmer in heavy small saucepan. Remove from heat. Add chocolate; whisk until melted and smooth. Cool chocolate until lukewarm but still pourable, about 5 minutes. Place cake on rack set over baking sheet. Pour half of glaze over top of cake. Spread glaze evenly over top and sides of cake. Freeze until glaze is set, about 10 minutes. If necessary, rewarm remaining glaze just until pourable. Pour remaining glaze over cake; spread glaze smoothly over top and sides of cake. Refrigerate cake until glaze is firm, about 2 hours. (Can be made 1 day ahead. Cover and keep chilled.) Let cake stand at room temperature at least 3 hours before serving. Transfer brownie cake to platter. Top cake with chocolate curls and garnish platter with mint sprigs and strawberries, if desired