Created by Fizzybrat on June 25, 2019
Step 1: Preheat oven to 350°F.
Step 2: Line a 13x9x2-inch baking pan with foil, extending the foil over edges of pan. Grease foil; set pan aside.
Step 3: For crust, in a small mixing bowl beat powdered sugar and the 1/2 cup softened butter with an electric mixer on low to medium speed until smooth.
Step 4: Beat in the 3/4 cup flour and the ground nuts until combined.
Step 5: Press mixture onto the bottom of the prepared baking pan.
Step 6: Bake for 12 minutes.
Step 7: Cool in pan on a wire rack.
Step 8: Place preserves in a blender or food processor.
Step 9: Cover and blend or process until smooth.
Step 10: Spread pureed preserves over crust.
Step 11: Chill for 20 minutes.
Step 12: Meanwhile, in a small saucepan cook and stir the unsweetened chocolate and the 1/2 cup butter over low heat until melted and smooth.
Step 13: Remove from heat; cool for 10 minutes.
Step 14: In a medium mixing bowl beat egg, egg yolk, granulated sugar, and salt on medium speed for 5 minutes.
Step 15: Beat in the melted unsweetened chocolate and vanilla. Stir in the 1/2 cup flour just until combined. Carefully spread mixture over chilled preserves layer.
Step 16: Bake for 20 minutes more. Cool in pan on a wire rack.
Step 17: Using the edges of the foil, lift uncut brownies out of pan.
Step 18: Spread brownies with melted semisweet chocolate; let stand until chocolate is set.
Step 19: Drizzle with melted white chocolate; let stand until white chocolate is set.
Step 20: Cut into bars.