Source: Salty's, Seattle, Washington

Makes one 9-inch cake.

Cake
3 cups cake flour, plus extra for dusting cake pans
1 tablespoon baking powder
1/2 teaspoon kosher salt
1 cup unsalted butter, at room temperature, cut into 8 pieces
2 cups granulated sugar
1 teaspoon vanilla extract
1 cup whole milk
8 large egg whites, at room temperature
1 pinch cream of tartar

Glaze
3 tablespoons red-currant jelly, whisked until it reaches spreading consistency

Icing
12 ounces white chocolate, coarsely chopped (see shopper's note)
4 cups whipping cream, chilled

Garnish
1 pound white chocolate, room temperature, shaved into curls (use
    vegetable peeler) or substitute sweetened coconut or white sprinkles

To prepare oven, baking pans: Preheat oven to 350 degrees F. Grease 3 (9-inch) cake pans. Line bottoms with wax or parchment paper. Grease paper. Dust bottoms and sides with flour. Tap out excess.

To mix cake: Sift together flour, baking powder and salt. Set aside. In large bowl and using electric mixer at low speed, beat together butter and sugar until coarsely blended. Increase speed to medium. Beat until light and creamy. Add vanilla, then flour mixture alternating with milk. Beat until well combined. In separate bowl, beat egg whites with cream of tartar at medium-high speed until they hold soft peaks. Using rubber spatula, gently fold one-third of egg whites into cake batter until well blended, using a cutting motion through middle of batter and turning bowl as you work. Gently fold remaining whites into batter until just combined. (Note: Do not over-mix.)

To bake cake: Divide batter evenly into prepared pans. Bake in center of oven for 25 to 30 minutes or until wooden pick inserted in center comes out clean. Cool layers in pans on wire racks for 20 minutes. Turn out onto racks to cool completely. Remove paper. Using serrated knife, cut off top brown part on each layer, making sure layers are flat and even.

To prepare mousse: In double boiler or stainless steel or glass bowl over saucepan filled with simmering water, heat 12 ounces white chocolate until almost melted. Remove pan from heat. Stir until completely melted. Cool to room temperature. Using electric mixer, whip cream in large mixing bowl until stiff peaks form. Working quickly, gently fold melted chocolate into cream.

To assemble: Place 1 cake layer on plate. Using pasty brush, quickly glaze top with thin layer of jelly. Working quickly, cover jelly with one-third of mousse. Top with cake layer. Add glaze and mousse. Top with final layer. Ice top and sides with remaining mousse. Gently press white-chocolate curls into mousse, covering entire cake. Refrigerate for at least 1 hour to set.

Shopper's note: When buying white chocolate, look for a product that contains cocoa butter and avoid those labeled as "artificial chocolate" or "chocolate-flavored."