Preheat oven to 300 degrees F. Place raspberries in the bowl of a food processor fitted with a metal blade. Pulse until liquefied, for about 1 minute. Strain the raspberries through a fine strainer, into a 5-quart bowl, using a rubber spatula to press down on the seeds to extract as much puree as possible (about 3/4-cup puree). Discard the seeds. Set the puree aside until needed. In a sifter, combine the flour, baking powder and salt. Sift onto a large piece of waxed paper and set aside until needed. Heat 1 inch of water in the bottom half of a double boiler over medium heat. Place the white chocolate and 4 ounces of butter in the top half. Use a rubber spatula to stir the chocolate and butter until completely melted and smooth, about 5 minutes. Transfer the melted white chocolate and butter into an empty 5 quart bowl and set aside until needed. Again, heat 1-inch of water in the bottom half of a double boiler over medium heat. Place the semisweet chocolate and the remaining 8 ounces of butter in the top half of the double boiler. Use a rubber spatula to stir the chocolate and butter until completely melted and smooth, about 7 minutes. Transfer the melted semisweet chocolate and butter to an empty 5-quart bowl and set aside until needed. Place the eggs, sugar, and vanilla extract in the bowl of an electric mixer, fitted with a balloon whip. Whisk on high for 2 minutes until soft. Use a rubber spatula to scrape down the sides of the bowl, then whisk on high for 4 minutes until slightly thickened and lemon colored. Operate the mixer on low while gradually adding the sifted dry ingredients until incorporated, about 30 seconds. Remove the bowl from the mixer and add the sour cream. Use a rubber spatula to mix the ingredients until thoroughly combined. Portion 2 cups of the batter into the bowl containing the pureed raspberries and stir until smooth. Portion 1 cup of the batter into the bowl containing the melted white chocolate mixture and stir until smooth. Portion the remaining 2 cups of batter into the bowl containing the melted semisweet chocolate mixture and stir until smooth. Pour the dark chocolate batter into a 9 by 13 by 2 inch nonstick baking pan and spread evenly over the bottom. Pour the white chocolate batter onto the top of the dark chocolate batter in swirls. Pour the raspberry batter over the other 2 batters in the same manner. Use the blade of a paring knife to swirl the batters together in a fanciful pattern (you should have fun doing this). Bake on the center rack of the preheated oven until a toothpick inserted in the center comes out clean, about 1 hour and 10 minutes. Remove the brownies from the oven and allow to cool in the pan at room temperature for 1 hour. Use a serrated knife with rounded tip to cut the brownies into 24 2-inch squares.;
Tip: To cut brownies well, use a serrated knife, with rounded tip. To make sure you get a clean cut, heat the blade of the knife under hot running water, and wipe the blade dry before making each cut. Tip: To decorate plates - in inexpensive, plastic squeeze bottles (like people use for ketchup), place flavored sauces - i.e. chocolate, butterscotch...whatever you like. Marcel's serving Tip: Refrigerate brownies for 2 to 3 hours before serving.;
Check Out Our
Get a sneak-peek of the new Food Network recipe page and give us your feedback.See it Now!