MAKE THE SPONGE CAKE: Preheat the oven to 170°C (340°F) and grease and line two 8-inch round cake pans with parchment paper.
SIFT DRY INGREDIENTS: In a medium bowl, sift together the cake flour, baking powder, and salt. Set aside.
BEAT EGGS AND SUGAR: In a large mixing bowl, beat the eggs and granulated sugar on high speed for 6 to 8 minutes until the mixture becomes pale, thick, and fluffy.
COMBINE LIQUID INGREDIENTS: In a small jug, stir together the warm milk, vegetable oil, and vanilla extract.
INCORPORATE LIQUIDS: With the mixer on low speed, gradually pour the milk mixture into the egg mixture until just combined.
FOLD IN DRY INGREDIENTS: Using a spatula, gently fold in the sifted flour mixture in two additions, mixing only until no streaks remain to avoid deflating the batter.
BAKE THE CAKES: Divide the batter evenly between the prepared pans and bake for 25 to 28 minutes, or until a toothpick inserted into the center comes out clean.
COOL COMPLETELY: Remove the cakes from the pans and let them cool fully on wire racks before assembling.
MAKE THE MANGO CREAM: In a chilled mixing bowl, beat the heavy cream with powdered sugar and vanilla extract until soft peaks form.
ADD MANGO PUREE: Gently fold the mango puree into the whipped cream until fully incorporated and smooth. Keep refrigerated until ready to use.
LEVEL THE CAKES: If needed, level the tops of the sponge cakes using a serrated knife to create even layers.
ASSEMBLE THE CAKE: Place one sponge layer on a serving plate. Spread a generous layer of mango whipped cream over the top.
ADD MANGO SLICES: Arrange thin slices of fresh mango evenly across the cream layer, covering the surface.
ADD SECOND CREAM LAYER: Spread a thin layer of mango cream over the mango slices to help the top layer adhere.
FINISH ASSEMBLY: Place the second cake layer on top and press down lightly to secure. Frost the top and sides with the remaining whipped cream.
DECORATE: Garnish the cake with additional mango slices arranged in a spiral or flower shape. Add mint leaves if desired for color contrast.
CHILL BEFORE SERVING: Refrigerate the assembled cake for at least 30 minutes before slicing to help the layers set and flavors meld.