In a food processor, pulse the pistachios to make a powder. In a large bowl, mix together the sunflower oil and caster sugar. Add the eggs, vanilla paste, ground cardamom and lemon zest.
Sieve in the flour, add the ground cardamom and baking powder and fold carefully into the batter so that no lumps of flour remain. Pour the mixture into the prepared tin. Peel and core the apples ...