Dissolve the sugar in water and boil it for five minutes. Add to the egg yolks, whisking them slowly. Cook on low heat till the mixture is light and reaches the ribbon stage. Remove from heat and keep aside to cool. When it reaches room temperature, add mango puree. Mix well and fold in the cream.
Decorate the glasses by putting a little chocolate on the sides. Pour the mixture into each glass, followed by mango dices. Repeat the layers. Chill for at least two to three hours in the deep freezer. Serve decorated with cream, mint leaves, a slice of mango and caramelised cashewnuts.