- Preheat oven to 180 C. Place the butter, sugar, flour and coconut in a bowl and mix to combine. Press the mixture into a 20cm x 30cm slice tin lined with non-stick baking paper. Bake for 15 minutes or until golden. Set aside. To make the topping, place the eggs and sugar in a bowl and beat with an electric mixer until pale and thick. Fold through the flour and baking powder and stir in the sultanas. Spread the topping over the base and bake for 25 minutes or until golden. Allow to cool in the tin and cut into squares to serve.