(CLASSIC CHEESECAKE BROWNIES)---Preheat oven to 350'F Grease 9" square baking pan, then line with 14"X8" sheet of parchment paper, overlapping parchment on two sides to form "handles.".
In a medium bowl, blend 1 cup of Mascarpone Cheese and 1 egg yolk; stir in 3 Tablespoons Sugar, 3 Tablespoons Flour until smooth, set aside.
In a large, heavy nonstick saucepan, melt 1 stick of butter, 2 oz chopped bittersweet or semisweet chocolate, stirring constantly over low heat until smooth. Remove from heat and stir in 1 cup sugar, 1 teaspoon vanilla extract and 2 large eggs until well blended. Stir in 2/3 cup flour until well blended.
Spread about 1/2 brownie batter into pan. Alternately spoon on Mascarpone and remaining brownie batter. Shake pan back and forth gently on countertop to level the batters. With the tip of a knife, swirl to marble mixtures.
Bake 30-35 minutes or until brownies just begin to pull from sides of pan. Cool completely in pan on rack. Chill before cutting for best results.
(FOR CHOCOLATE SIN MASCARPONE BROWNIES).-----Add 1/2 cup semisweet chocolate chips to brownie batter at end of STEP 3; bake and cool as directed. Meanwhile, blend 1 cup semisweet chocolate chips, 2 Tablespoons confectioner's sugar and 1/2 cup Creme Fraiche in a small heavy saucepan over low heat. Stir constantly until smooth. Pour glaze over brownies and chill until set.
(FOR DOUBLE TOFFEE MASCARPONE BROWNIES)------Add 2 Teaspoons espresso powder to brownie batter with sugar in STEP 3 mix as directed, then stir in 1/2 cup chopped hard toffee candy such as Heath or Werther's. Bake and cool as directed. Meanwhile, in a small bowl, beat 1/2 cup Creme Fraiche with 3 Tablespoons confectioner's sugar until soft peaks form; stir in another 1/4 cup reserved toffee. Serve immediately over brownies.
(FOR BOURBON PECAN MASCARPONE BROWNIES).-----Add 2 Tablespoons bourbon and 1/2 cup chopped pecans to brownie batter after STEP 3; bake and cool as directed. Meanwhile in a small saucepan, combine another 2 Tablespoons bourbon, 1/2 cup Creme Fraiche and 1/2 cup light brown sugar. Cook over medium heat, stirring constantly, 5 minutes. Chill sauce before drizzling over brownies.