Preheat the oven to 350°F (180°C). Grease an 8-inch pan and line it with parchment paper.

In a large bowl, whisk eggs and sugar until thick and pale (about 10 minutes).

Gently fold in ground pistachios, flour, and melted butter.

Pour the batter into the pan and bake for 15-17 minutes. Let it cool completely.

In a saucepan, combine raspberries, sugar, and lemon juice. Cook over medium heat until it thickens (about 5 minutes) and strain to remove seeds.

Dissolve the gelatin in cold water and mix it into the warm raspberry sauce.

Melt white chocolate and cream together using a bain-marie, then stir in chopped pistachios.

Line an 8-inch cake ring with acetate and place it on a serving platter. Add the cooled pistachio cake, spread the chocolate mixture evenly, and chill.

Whip the chilled cream until stiff peaks form, then fold in the cooled raspberry mixture. Pour over the chocolate layer and refrigerate for 30 minutes.

Blend mango slices into a smooth puree, sweeten with sugar, and mix in the dissolved gelatin. Whip cream until soft peaks form and fold in the mango mixture.

Pour the mango mousse over raspberry mousse and chill for 4 hours or overnight.

Cook raspberries and sugar over medium heat for 2 minutes, strain, and mix in dissolved gelatin. Pour over the mango mousse and chill for 2-3 hours until set.