PreparationFor Brownies: Preheat oven to 350°F. Butter 13x9x2-inch glass baking dish. Combine 1 cup butter and semisweet and unsweetened chocolates in heavy medium saucepan. Stir over low heat until chocolates melt and mixture is smooth. Cool to lukewarm. Using electric mixer, beat sugar and 3 eggs in large bowl until very thick and pale, about 3 minutes. Stir in chocolate mixture and vanilla extract. Whisk 1 cup flour, baking powder and salt in medium bowl to blend. Stir dry ingredients into chocolate mixture. Mix in walnuts and dried fruits. Transfer batter to prepared dish; smooth top. Bake until top cracks and tester inserted into center comes out with a few moist crumbs attached, about 35 minutes. Cool in pan on rack. For frosting: Combine room temperature cream cheese, butter and vanilla extract in processor. Blend until smooth, scraping down sides of bowl occasionally. Add sugar and process to blend. Spread frosting over brownies. Refrigerate until frosting is well chilled, about 2 hours. (Can be prepared 3 days ahead. Cover; keep refrigerated.) Cut brownies into squares. Arrange on platter; garnish with walnuts, if desired, and serve.
PreparationFor Brownies: Preheat oven to 350°F. Butter 13x9x2-inch glass baking dish. Combine 1 cup butter and semisweet and unsweetened chocolates in heavy medium saucepan. Stir over low heat until chocolates melt and mixture is smooth. Cool to lukewarm. Using electric mixer, beat sugar and 3 eggs in large bowl until very thick and pale, about 3 minutes. Stir in chocolate mixture and vanilla extract. Whisk 1 cup flour, baking powder and salt in medium bowl to blend. Stir dry ingredients into chocolate mixture. Mix in walnuts and dried fruits. Transfer batter to prepared dish; smooth top. Bake until top cracks and tester inserted into center comes out with a few moist crumbs attached, about 35 minutes. Cool in pan on rack. For frosting: Combine room temperature cream cheese, butter and vanilla extract in processor. Blend until smooth, scraping down sides of bowl occasionally. Add sugar and process to blend. Spread frosting over brownies. Refrigerate until frosting is well chilled, about 2 hours. (Can be prepared 3 days ahead. Cover; keep refrigerated.) Cut brownies into squares. Arrange on platter; garnish with walnuts, if desired, and serve.