Heat oven to 350 degrees F. Grease 9-inch springform pan; flour.
Finely grind hazelnuts in food processor. Add flour; pulse to combine. Remove and reserve.
Melt butter in small saucepan. Whirl German and semisweet chocolates in processor until powdered. With machine running, add butter until smooth. Add sugar, eggs and vanilla. Whirl until smooth. Add flour mixture. Whirl to combine.
Scrape into springform pan; spread level. Arrange berries on top, pressing lightly into batter.
Bake in 350 degree F oven 50 to 60 minutes or until center is set. Cool cake in pan on wire rack 10 minutes. Remove sides of pan. Cool cake completely. (Can be made up to 2 days ahead; wrap and refrigerate.)
Knead paste until smooth. Dust 2 sheets of waxed paper with confectioners sugar. Roll paste out to 9-inch circle between sheets. Place on top of cake; trim excess. Place cake on rack over waxed-paper-lined jelly-roll pan.
Heat cream and espresso in saucepan just to simmer. Remove from heat. Add chocolate. Cover; let stand 10 minutes. Stir until smooth. Let stand until thin frosting consistency. Spoon over cake, spreading to coat.
Place white chocolate and semisweet chocolate in 2 separate bowls. Add tablespoon cream to each. Microwave at 100 percent power 30 seconds to melt. (Or melt in saucepans.) Scrape into separate small plastic bags, pushing into corner; snip off tiniest corner. Starting from center of cake, with white chocolate, pipe spiral, spacing lines 1 inch apart. Pipe bittersweet spiral, between white spiral. Using tip of sharp knife, draw through piped lines, spoke fashion, starting from center, going to edge of cake, alternating with strokes drawn from outer edge to center. Let stand for chocolate to harden.
Remove cake from bottom of pan to serving plate. (Cake can be refrigerated, airtight, up to 2 days.) Makes 16 servings.