Bake cake until brown and tester inserted into center comes out clean, about 1 hour 25 minutes. Cool cake in pan on rack 30 minutes. Cut around cake to loosen; remove pan sides. Maintain oven temperature.
Make second batch of cake batter following same technique as for first cake and using same amount of each ingredient. Transfer 8½ cups batter to prepared 9-inch pan; transfer 4 cups batter to prepared 6-inch pan. Bake cakes until brown and tester inserted into centers comes out clean, about 1 hour 10 minutes for 6-inch cake, and about 1 hour 18 minutes for 9-inch cake. Cool cakes in pans on racks 30 minutes. Cut around cakes to loosen. Remove pan sides. Let cakes stand until cooled completely.
DO AHEAD: Can be made 1 day before filling and frosting the cakes. Return cakes to pans. Cover with foil and store at room temperature.
Assembling Cakes
To make filling and frosting the cakes easier, use the removable bottoms of tart pans or buy cardboard rounds from a cake or candy supply store.
2 11-inch-diameter tart-pan bottoms or cardboard rounds
1 8-inch-diameter tart-pan bottom or cardboard round (cut from 9-inch round)
1 5-inch-diameter tart-pan bottom or cardboard round (cut from 6-inch round)
14 12-inch-long, ¼-inch-diameter wood dowels
Push 12-inch cake up to release from pan. Using large serrated knife, cut off enough of top crust to make cake 2½ inches high. Cut cake horizontally into 3 layers, each about ¾ inch thick. Using tart-pan bottom or 11-inch-diameter cardboard round, transfer top layer of cake to work surface and cover; transfer middle layer of cake to work surface and cover. Cut bottom layer of cake from pan bottom and place on tart-pan bottom or cardboard round. Spread generous 1¾ cups mousse over. Drop 1¾ cups curd over by table-spoonfuls and spread to cover mousse in even layer. Chill until mousse and curd are firm, about 1 hour. Using tart-pan bottom, place middle layer of cake atop bottom layer. Spread with same amounts of mousse and curd. Using tart-pan bottom, place top layer of cake atop middle layer and press lightly. Chill assembled cake.
Push 9-inch cake up to release from pan. Cut off enough of top crust to make cake 2½ inches high. Cut cake horizontally into 3 layers, each about ¾ inch thick. Using tart-pan bottom or cardboard round, transfer top layer of cake to work surface and cover; repeat with middle layer of cake. Cut bottom layer of cake from pan bottom and place on 8-inch-diameter tart-pan bottom or cardboard round. Spread 1¼ cups mousse over. Drop generous ⅔ cup curd over by tablespoonfuls and spread to cover mousse in even layer. Chill until mousse and curd are firm, about 1 hour. Using tart-pan bottom, place middle layer of cake atop bottom layer. Spread with same amount of mousse and curd. Using tart-pan bottom, place top layer of cake atop middle layer and press lightly. Chill assembled cake.
Push 6-inch cake up to release from pan. Cut off enough of top crust to make cake 2½ inches high. Cut cake horizontally into 3 layers, each about ¾ inch thick. Transfer top layer of cake to work surface and cover; repeat with middle layer of cake. Cut bottom layer of cake from pan bottom and place on 5-inch-diameter tart-pan bottom or cardboard round. Spread generous ½ cup mousse over. Drop 6 tablespoons curd over by tablespoonfuls and spread to cover mousse in even layer. Chill until mousse and curd are firm, about 1 hour. Using large spatula, place middle layer of cake atop bottom layer. Spread with same amount of mousse and curd. Using large spatula, place top layer of cake atop middle layer and press lightly. Chill assembled cake.
Spread 2¼ cups frosting thinly over top and sides of 12-inch assembled cake. Spread 1½ cups frosting thinly over top and sides of 9-inch assembled cake. Spread ¾ cup frosting thinly over top and sides of 6-inch assembled cake. Chill cakes 1 hour.
Spread 5 cups frosting over 12-inch cake. Spread 3⅔ cups frosting over 9-inch cake. Spread 2 cups frosting over 6-inch cake. Chill 6-inch cake.
Place 12-inch cake on platter. Press 1 dowel into center and through to bottom of cake. Mark dowel 1¼ inches above level of frosting. Remove dowel and cut with serrated knife at marked point. Cut 7 more dowels to same length. Press 1 dowel into center of cake. Press remaining 7 dowels into cake, spacing apart equally, 3 to 3¼ inches from center dowel. Chill cake with dowels.
Press 1 dowel into center of 9-inch cake. Mark dowel 1¼ inches above level of frosting. Remove dowel and cut with serrated knife at marked point. Cut 5 more dowels to same length. Press 1 dowel into center of cake. Press remaining 5 dowels into cake, spacing apart equally, 2 inches from center. Chill cake with dowels in place.
DO AHEAD: Can be made 2 days ahead. After frosting is firm, cover cakes with cake domes or loosely with foil; keep chilled.
Assembly and Decoration
Mix of large and tiny white roses and freesias (about 5 dozen)
Place 9-inch cake atop dowels in 12-inch cake. Place 6-inch cake atop dowels in 9-inch cake. Place large roses between bottom and middle tiers, fitting in tiny roses and freesias to fill space. Fill space between middle and top tiers with mix of flowers.
Berry Compote
Makes about 16 cups
8 1-pint containers strawberries, hulled, halved
2½-pint containers blackberries
2½-pint containers raspberries
2½-pint containers blueberries
1 cup sugar
Combine all berries and sugar in large bowl; toss to coat. Cover; chill until juices form, at least 1 hour and up to 6 hours.
SERVING: Place top and middle cake tiers on work surface. Remove flowers and dowels from cakes. Cut top cake into 8 slices. Cut middle cake into 16 slices. Insert knife straight down into 12-inch cake 3 inches from edge. Continue to cut around cake 3 inches from edge, making 6-inch-diameter circle in center. Cut outer ring into 18 slices. Cut 6-inch center into 8 slices. Place cake slices on plates; spoon compote alongside each.
Tiered Cake TimelineDon’t wait until the last minute to make multi-tiered cakes—it’s not like baking a simple batch of cupcakes. But a bit of timing and planning makes baking multiple cakes completely manageable. Since each cake recipe includes suitable do-aheads, abide by their guidelines to ensure the best results. When in doubt, this breakdown can help you map out each step.
7 days before the event, have all your ingredients and equipment on hand.
5 days ahead, clear enough room in the refrigerator to store the filling, frostings, and cakes.
4 days before the event, make the frosting and fillings.
3 days ahead, bake the cakes and store them properly to maintain freshness.
2 days ahead, fill and frost the cakes, and insert dowels into the bottom tiers.
1 day ahead, buy fresh flowers (if using). Stand the flowers in water and refrigerate.
4 hours before the event, transport the cakes and assemble them upon arrival. Bring extra frosting and tools, such as offset spatulas and piping bags.
Any time one dessert features three forms of chocolate—chocolate cake, chocolate ganache, and chocolate mousse—there’s going to be a celebration. Serve this stunning dessert at a bridal shower, a graduation, on Father’s Day, or for any other summertime occasion when berries are full of flavor. Begin making the cake one day ahead; you’ll need a 9-inch tart pan bottom or cardboard round when you assemble the cake. Enjoy the extra mousse and cake later with fresh berries. 20 servings