For Lemon Curd Filling: Sprinkle gel a tin over 2 tsp water in small bowl. Let stand 10 minutes to soften. Blend sugar and lemon peel in processor 2 minutes. Transfer lemon peel mixture to heavy medium saucepan. Whisk in lemon juice and yolks. Add butter and cook over medium heat until mixture thickens and leaves path on back of spoon when finger is drawn across, stirring constantly, about 7 minutes; do not boil. Remove from heat. Add gelatin mixture and stir until dissolved. Cover and refrigerate until well chilled. (Can be prepared 3 days ahead; keep refrigerated.)

For Cake: Position rack in lowest third of oven and preheat to 350°F. Butter and flour 9-inch-diameter springform pan with 23/2 3/4-inch-high sides. Sift flour, potato starch and baking powder into medium bowl. Using electric mixer, beat eggs and sugar in large bowl until mixture is very thick and slowly dissolving ribbon forms when beaters are lifted, about 7 minutes. Mix in lemon peel. Sift dry ingredients over egg mixture in 3 additions, folding in after each addition. Pour into prepared pan. Bake until tester inserted into center comes out clean, about 30 minutes. Cool cake in pan on rack 20 minutes. Run small sharp knife around pan sides to loosen cake if necessary. Release pan sides. Cool cake completely. (Can be made 1 day ahead. Wrap tightly and let stand at room temperature.)

For Frosting: Beat cream and sugar in large bowl to stiff peaks. Run long thin knife between cake and pan bottom to loosen cake. Cut cake horizontally into 3 even layers. Place bottom cake layer on plate. Spoon 1/3 cup thawed sweetened berries with juices over cake. Carefully spread generous 1/3 cup lemon curd over. Top with single layer of sliced fresh strawberries. Spread 1 cup whipped cream frosting over. Top with second cake layer and repeat layering process, using 1/3 cup thawed sweetened berries, generous 1/3 cup lemon curd, single layer of sliced fresh berries and 1 cup whipped cream frosting. Top with third cake layer. Spoon 3 tablespoons thawed berry juices over. Spread 1/3 cup curd over top of cake (reserve any remaining curd for another use).

Spread 2 1/2 cups whipped cream over top and sides of cake. Spoon remaining whipped cream into pastry bag fitted with medium star tip. Pipe cream in vertical columns around sides of cake from top edge to bottom. Pipe rosettes of cream around top edge of cake. Arrange 8 fanned strawberries around edge of cake. Fill center with blueberries. Refrigerate at least 3 and up to 6 hours before serving.

A classic Swedish dessert. To create the decorative strawberry fans, make several lengthwise cuts in each berry, starting just below stem and extending through tip. Also serve butter cookies and fresh fruit.

Serves: 10 Servings