Whisk egg yolks with 60g caster sugar in a bowl until thick.
Boil remaining caster sugar, milk, cream, vanilla seeds, and pods in a pan.
Stir hot milk into yolks and cook over low heat until thickened.
Cool and refrigerate mixture for one hour before churning in an ice cream maker.
Preheat oven to 180°C and scatter 150g blackberries across a lined 24cm tin.
Melt chocolate and 150g butter in a bowl over simmering water and cool slightly.
Whisk six egg yolks with two tablespoons of sugar in a mixing bowl.
Whisk egg whites in a separate bowl to firm peaks while gradually adding remaining sugar.
Combine melted chocolate with yolks and gently fold in the egg whites.
Pour batter into the tin and bake for 20-25 minutes at 180°C until springy.
Cool the cake completely on a wire rack.
Melt 50g butter, cook 125g blackberries for two minutes, and serve with cake and ice cream.