Creating the Mango Mousse Cake is a straightforward process if you follow these simple steps:

1. Prepare the Gelatin: In a small bowl, sprinkle the gelatin over cold water. Let it sit for about 5 minutes to bloom.
2. Dissolve the Gelatin: After blooming, gently heat the mixture in the microwave for 10-15 seconds until the gelatin is completely dissolved. Set aside to cool slightly.
3. Blend the Mangoes: In a blender, puree the diced mangoes until smooth. Measure out 1 cup of mango puree and set aside.
4. Whip the Cream: In a mixing bowl, whip the heavy cream until soft peaks form. Be careful not to over-whip, as it can become grainy.
5. Mix Cream Cheese and Sugar: In another bowl, beat the softened cream cheese and powdered sugar together until smooth and creamy. Add the vanilla extract and mix well.
6. Combine Mango and Cream Cheese: Fold the mango puree into the cream cheese mixture until fully combined.
7. Add Gelatin: Gradually fold in the cooled gelatin mixture, ensuring it is well incorporated.
8. Fold in Whipped Cream: Gently fold the whipped cream into the mango mixture, being careful to maintain the light and airy texture.
9. Assemble the Cake: Place the sponge cake in a springform pan. Pour half of the mango mousse mixture over the cake, spreading it evenly.
10. Layer Again: Add another layer of sponge cake on top of the mousse, followed by the remaining mousse mixture. Smooth the top with a spatula.
11. Chill: Cover the cake with plastic wrap and refrigerate for at least 4 hours, or overnight for best results.
12. Release the Cake: Once chilled and set, gently release the sides of the springform pan.
13. Garnish: Top the cake with fresh mango slices and mint leaves if desired before serving.

These steps will guide you through creating this delightful Mango Mousse Cake with ease.