Lemon Mousse Cake

Made this birthday cake over the weekend. But wasn't really satisfied with the decorating.. This cake is quite light because of the mousse but it's abit sourish.. don't know is it because my sugar was too less? If you like something sweeter you can add more sugar.. I prefer somewhere there, not too sweet.

Lemon Mousse Cake

8 inch cake pan (serve 10)

 Lemon Mousse Cake

Genoise: 100 g sifted cake flour 1/8 teaspoon salt 4 large eggs 100 g granulated sugar 1 teaspoon finely grated lemon zest 1 teaspoon vanilla extract 57 g unsalted butter, melted and cooled Ginger Syrup: (I omitted the ginger) 160 ml water 100 g granulated sugar 1/2-inch piece fresh gingerroot, peeled and thinly sliced Lemon Mousse: 60 ml water 2  teaspoons powdered gelatin 1 cup freshly squeezed lemon juice 1 1/2 tablespoons (9 g) finely grated Meyer lemon zest 225 g granulated sugar 6 large egg yolks 30 ml Grand Marnier or Cointreau (optional) 1 teaspoon vanilla extract 360 ml heavy cream Garnish: Candied Lemons Make the genoise: Position a rack in the center of the oven and preheat the oven to 180C. Grease the bottom and sides of a 8-inch round cake pan. Dust the pan with flour and set aside. In a medium bowl, sift together the cake flour and salt. Whisk to combine and set aside. In the bowl of an electric mixer, whisk together the eggs and sugar by hand. Set the bowl over a saucepan of simmering water, making sure that the bottom of the bowl does not touch the water. Heat the egg mixture, whisking constantly, until the eggs are warm. Transfer the bowl to the electric mixer stand and, using the whisk attachment, beat on high speed until the mixture has tripled in volume, about 8 minutes. Reduce the speed to low and beat in the lemon zest and vanilla extract. Resift one-third of the flour mixture over the batter and gently fold it in with a rubber spatula. In two more additions, sift in the remaining flour mixture, again folding in gently. Have the melted butter in a small bowl. Scoop about 3/4 cup of the cake batter into the bowl and stir until blended. Fold this mixture into the remaining cake batter. Scrape the batter into the prepared pan. Bake the cake for 18 to 22 minutes, until the top springs back when lightly touched and a tester inserted into the center comes out clean. Cool the cake in the pan for 15 minutes. Invert the cake onto the wire rack and cool completely. Make the Syrup: In a small saucepan, combine the water and sugar and bring to a boil over medium-high heat, stirring occasionally just to dissolve the sugar. Remove the pan from the heat and add the ginger slices. Let stand at room temperature until ready to use. Make the mousse: Pour the water into a medium saucepan and sprinkle the gelatin over it. Let the gelatin soften for 5 minutes. Whisk in the lemon juice,  zest, sugar, and egg yolks. Place the pan over medium heat and cook, whisking constantly, until the mixture thickens and reaches 82C on an instant-read thermometer. Pour the mixture through a fine-mesh sieve into a medium bowl. Stir in the orange liqueur and vanilla extract. Set the bowl containing the lemon mixture in a large mixing bowl filled one-third of the way with ice water (be careful that the water doesn’t splash into the lemon mixture). Stir the lemon mixture frequently until it is completely cool, about 10 minutes. In the bowl of an electric mixer, using the whisk attachment, whip the heavy cream at medium-high speed to firm peaks. Fold the lemon mixture into the whipped cream. Assemble the cake: Using a long serrated knife or cake cutter, cut the genoise cake horizontally into 2 layers. Arrange a cake layer, cut side up, in the bottom of a 9-inch springform pan, centering it so that the gap between the cake and the side of the pan is even all the way around.  Generously brush the cake with half of the Ginger Syrup. Scrape half of the mousse on top of the cake and, using a small offset metal spatula, spread it into an even layer, letting the mousse fill the gap between the cake and the side of the pan. Arrange the remaining cake layer, cut side up, on top, centering it. Brush the cake with the remaining Ginger Syrup. Scrape the remaining mousse on top and spread it into an even layer as before. Refrigerate the cake for at least 3 hours before serving, until set.