1-Preparing the Orange Chiffon Cake: First, sift together 1 cup plus 2 tablespoons all-purpose flour, 3/4 teaspoon baking powder, 1/2 cup plus 3 tablespoons sugar, and 1/2 teaspoon kosher salt in a large bowl. In another bowl, whisk 1/4 cup vegetable oil with 3 large egg yolks, 1/2 cup plus 2 tablespoons orange juice, 1/4 teaspoon orange extract, and 1 teaspoon orange zest until smooth. Beat 5 large egg whites with 1/4 teaspoon cream of tartar until stiff peaks form, then gently fold this into the wet mixture. Pour the batter into a prepared pan and bake as directed, cooling the cake inverted to prevent shrinking.

2-Next, move on to the pastry cream filling by heating 1 cup whole milk with 1/2 teaspoon vanilla extract and 1/8 teaspoon kosher salt in a saucepan. In a separate bowl, mix 2 tablespoons cornstarch, 1/4 cup sugar, and 2 egg yolks, then temper this with the hot milk mixture. Cook until thickened, add 2 tablespoons unsalted butter, and incorporate softened gelatin mixed with 1/2 tablespoon water. Finally, fold in whipped 1 cup heavy cream for a light texture that’s perfect for layering.

3-Making the Candied Orange Peel and Kumquats: While the cake cools, prepare the candied elements by zesting and slicing 1 orange and 12 kumquats. Boil the strips a few times to soften them, then simmer in a syrup of 1 cup sugar and 1 1/2 cups water until translucent. Let them cool in the syrup for added flavor. For the white chocolate ganache, heat 1/4 cup heavy cream to boiling, pour it over 6 ounces chopped white chocolate, and stir until smooth, then chill for 24 hours to thicken remember, preparing this ahead ensures the best firmness.

4-Assembling the Cake: Now for assembly: Slice the baked 9-inch chiffon cake horizontally and moisten the layers with 1/3 cup simple syrup, perhaps using the syrup from your candied fruit for extra citrus notes. Line your pan with plastic wrap, place halved strawberries cut-side out along the edges, and fill between layers with the pastry cream mixture, incorporating sliced strawberries and mango. Top with the second cake layer, more cream, and the white chocolate ganache. Refrigerate for at least 4 hours to set everything firmly. This step-by-step approach, including tips like using extra whipped cream for a firmer filling, makes the process straightforward and adaptable for busy schedules.