Prepare the Coconut Sponge

1. Preheat Oven: Preheat your oven to 350°F (175°C). Line an 8-inch round cake pan with parchment paper and lightly grease the sides.
2. Whisk the Eggs: In a large bowl, whisk the eggs and sugar until light and fluffy, about 5 minutes. This is crucial for creating a light and airy sponge.
3. Add Dry Ingredients: Sift the flour, baking powder, and shredded coconut into the egg mixture. Gently fold everything together with a spatula.
4. Incorporate Wet Ingredients: Slowly fold in the melted butter, coconut milk, and vanilla extract, ensuring the mixture is smooth and well combined.
5. Bake: Pour the batter into the prepared cake pan and bake for 20-25 minutes, or until a toothpick inserted into the center comes out clean. Allow the sponge to cool completely before removing it from the pan.

Make the Mango Mousse

1. Prepare Gelatin: Sprinkle the gelatin powder over 1/4 cup cold water and let it bloom for about 5 minutes.
2. Heat Mango Puree: In a saucepan, gently heat the mango puree and sugar over medium heat. Stir constantly to avoid burning.
3. Dissolve Gelatin: Once the mango mixture is warm, remove it from the heat and add the bloomed gelatin, stirring until completely dissolved.
4. Whip the Cream: In a separate bowl, whip the heavy cream until soft peaks form. Be careful not to overwhip.
5. Combine: Gently fold the whipped cream into the mango mixture, then add lemon juice. Mix until smooth and well incorporated.

Make the Coconut Gelée

1. Prepare Gelatin: Sprinkle the gelatin powder over 1/4 cup cold water and let it bloom for about 5 minutes.
2. Heat Coconut Water: In a saucepan, combine the coconut water and sugar, and heat gently until the sugar dissolves.
3. Add Gelatin: Once the coconut water mixture is warm, add the bloomed gelatin and stir until completely dissolved. Remove from heat and stir in the coconut milk.
4. Set the Gelée: Pour the coconut gelée into a shallow dish or small molds and let it chill in the refrigerator until set, about 1 to 1.5 hours.

Assemble the Entremet

1. Cut the Sponge: Once the coconut sponge has cooled, cut it into small discs that will fit into your individual serving molds or a single large mold.
2. Layer the Sponge: Place one disc of coconut sponge at the bottom of each mold. Pour the mango mousse over the sponge, smoothing the top with a spatula. Let it chill in the refrigerator for 1 hour to set.
3. Add the Coconut Gelée: Once the mousse has set, cut the coconut gelée into small pieces and arrange them over the mousse layer. Top with a final layer of mango mousse.
4. Chill: Allow the entremet to chill for another 1 to 1.5 hours, until fully set.

Garnish and Serve

1. Prepare the Garnish: Slice fresh mango into thin strips, toast some coconut flakes, and gather mint leaves for garnish.
2. Unmold the Entremet: Carefully remove the entremet from the mold and place it on a serving platter.
3. Decorate: Arrange the fresh mango slices and toasted coconut flakes on top of the entremet. Add mint leaves for a pop of color if desired.
4. Serve: Slice and serve chilled, enjoying the tropical layers of flavor and texture!