Mango Layer:

1. Prepare the Mango Puree: Puree ripe mangoes in a blender until smooth to make about 2 cups of puree.
2. Bloom the Gelatin: In a small bowl, sprinkle 1 teaspoon of gelatin over 2 tablespoons of warm water. Let it sit for about 10 minutes. This process is called blooming and it helps the gelatin dissolve evenly.
3. Combine Gelatin and Mango: Gently warm the mango puree in a saucepan over low heat. Add the bloomed gelatin to the mango puree and stir until the gelatin is fully dissolved.
4. Set the Mango Layer: Pour the mango mixture into glasses or molds, tilting them slightly for a diagonal layer if desired. Place in the refrigerator and chill for about 4 hours, or until the layer is set.

Cream Layer:

1. Bloom More Gelatin: In a separate bowl, bloom 1.5 teaspoons of gelatin in 2 tablespoons of warm water, similar to the first layer.
2. Prepare the Cream Mixture: In a saucepan, combine the heavy cream, whole milk, and granulated sugar. Heat the mixture gently over low heat until the sugar dissolves. Avoid boiling.
3. Combine Gelatin and Cream Mixture: Add the bloomed gelatin to the warm cream mixture. Stir until the gelatin is completely dissolved.
4. Add Cream Layer to Set Mango Layer: Once the mango layer is set, gently pour the cream mixture over it. Be careful to not disturb the set mango layer.
5. Chill to Set: Refrigerate the dessert for another 4 hours, or until the cream layer is firm.