Rub butter into sifted flour and salt, then mix with beaten eggs to form a dough ball and chill for 45 minutes.
Preheat the oven to 180°C and grease a 29cm pie tin.
Boil blueberries, apple juice, sugar, vanilla, and cinnamon for four minutes, then stir in pectin and cornflour.
Roll pastry to 0.5cm thickness and transfer it into the greased tin.
Bake the pastry blind with weights for 15 minutes, then bake for 12 minutes more until golden and cool.
Boil raspberries, sugar, and lemon juice for 4 minutes and strain through a sieve.
Whisk soaked gelatine and whipped cream into the raspberry mixture and chill until semi-set.
Spread the blueberry jam onto the cold pastry base and chill to set.
Whip cold double cream with icing sugar and vanilla until soft peaks form and place in a piping bag.
Pour raspberry filling over the jam, smooth the top, and chill for 30 minutes until set.
Simmer raspberry and blueberry coulis ingredients separately with 100ml water and cornflour until thickened, then strain and cool.
Pipe Chantilly cream rosettes in concentric circles on top of the set filling.
Pipe raspberry coulis swirls on half the rosettes and blueberry coulis on the other half.
Garnish with fresh berries and chill before serving.