Raspberry Charlotte Cake – A Classic French Dessert

Method

1. Make the raspberry syrup: In a medium saucepan, combine 10 oz frozen raspberries and 1/2 cup sugar. Cook over medium heat, stirring occasionally, until the mixture reaches a jam-like consistency. Remove from heat and strain through a fine-mesh sieve, pressing the fruit with a spoon to extract as much juice as possible (you should get about 2/3 cup syrup).
2. Stir 2 Tbsp lemon juice and 1 Tbsp gelatin into the raspberry syrup. Return the mixture to the saucepan and place over medium heat, whisking constantly until the gelatin is fully dissolved. Do not let it boil. Remove from heat and let cool to room temperature.
3. Make the sponge cake: Preheat the oven to 350°F. Line a 9-inch springform pan with parchment paper. In the bowl of a stand mixer fitted with the whisk attachment, beat 4 eggs on high speed for 1 minute. Gradually add 2/3 cup sugar and continue beating on high for 7 minutes, until the mixture is thick and has tripled or quadrupled in volume.
4. In a small bowl, stir together 2/3 cup cake flour and 1/4 tsp baking powder. Sift the flour mixture over the whipped eggs in two additions, folding gently with a spatula after each addition. Scrape the bottom of the bowl to incorporate any hidden pockets of flour, and fold just until combined—do not overmix. Pour the batter into the prepared pan and bake for 23–25 minutes, until the top is golden and springs back when lightly touched.
5. Remove the cake from the oven. Run a thin spatula around the edges to loosen it, then transfer the cake to a wire rack. Peel off the parchment paper and let cool completely. Once cool, slice the cake horizontally into two even layers.
6. Assemble the charlotte: Line the sides of the springform pan with plastic wrap. Trim about 1/2 inch off the edges of both cake layers (use kitchen scissors if desired). Place one cake layer in the bottom of the pan. Trim about 1/2 inch off one end of each ladyfinger, then arrange them tightly around the cake base, cut-side down. Brush the cake layer with one-third of the simple syrup, and also brush the backs of the ladyfingers with one-third of the syrup. Spread 1 1/2 Tbsp raspberry preserves over the cake. Set aside.
7. Make the whipped cream: In a large bowl, beat 3 cups heavy cream and 6 Tbsp powdered sugar with the whisk attachment on high speed until thick and spreadable. Transfer 1 1/2 cups of the whipped cream to a piping bag fitted with a star tip and refrigerate for later use as topping.
8. Make the mousse: Once the raspberry syrup has cooled to room temperature (do not wait too long, or it will thicken and become difficult to blend), fold it into the remaining whipped cream in four additions, folding gently after each addition until fully incorporated.
9. Spread half of the mousse over the cake layer inside the springform. Place the second cake layer on top, brush with the remaining simple syrup, and spread with the remaining 1 1/2 Tbsp raspberry preserves. Add the remaining mousse on top. Pipe the reserved whipped cream over the mousse, and garnish with fresh raspberries and mint leaves. Cover with plastic wrap and refrigerate for at least 3 hours or overnight until set. To serve, remove the springform sides and plastic wrap.