Preheat the oven to 350°F (175°C).

Grease and line the bottom of an 8-inch springform pan with parchment paper.

Beat the eggs until foamy.

Gradually add the sugar and continue beating for 7–10 minutes until thick and tripled in volume.

Sift together the flour and baking powder.

Gently fold the flour mixture into the egg mixture.

Pour the batter into the prepared pan.

Cool completely on a wire rack.

Return the cake to the springform pan.

Combine water and sugar in a saucepan.

Bring to a boil until the sugar dissolves.

Cool completely.

Lightly brush the sponge cake with the syrup.

Make the Mango Mousse

Whip the heavy cream and icing sugar until stiff peaks form.

Fold the whipped cream into the mango puree.

In a small bowl, sprinkle gelatin over water and allow it to bloom.

Microwave for about 15 seconds until dissolved.

Cool slightly.

Mix a small amount of mango cream mixture with the gelatin to temper it.

Fold the gelatin mixture into the remaining mousse.

Pour the mousse over the sponge cake.

Smooth the top evenly.

Refrigerate for at least 8 hours or overnight.

Stir sugar into the mango puree.

Bloom the gelatin in water.

Microwave until dissolved.

Temper with a small amount of mango puree.

Mix back into the remaining puree.

Gently pour over the chilled mousse layer.

Refrigerate for another 2–4 hours until set.

Carefully remove the springform ring.

Slice and serve chilled.