Preheat your oven to 350°F (175°C). In a mixing bowl, combine pistachio flour and granulated sugar. Add in eggs, melted butter, and vegetable oil. Pour the batter into a greased cake pan and bake for about 25 minutes.

While the cake cools, melt white chocolate in a heatproof bowl over simmering water. In a separate bowl, whip heavy cream until soft peaks form. Fold cooled white chocolate into whipped cream.

For the raspberry mousse, heat raspberry puree and sugar in a saucepan until the sugar dissolves. Soften gelatin in warm water and add to the mixture. Cool slightly and fold in whipped cream.

Repeat for the mango mousse, heating mango puree with sugar, adding softened gelatin, and folding in whipped cream once cooled.

Layer the cake: spread white chocolate mixture over the cooled pistachio cake, followed by raspberry mousse, and then mango mousse. Repeat layers if desired.

Chill the assembled cake in the refrigerator for at least 4 hours. Spread raspberry jelly on top before serving.