Makes about 30
100g fresh pistachios (or unsalted kernels), shelled
150g caster sugar
190g plain flour
90g fine polenta flour
¾ tsp baking soda
50g unsalted butter, melted
zest of a small orange, finely grated
zest of a small lemon, finely grated
Preheat the oven to 160oC. Spread pistachio kernels on a tray and roast for 8-10 minutes till perfumed. Remove from the oven and cool. Increase temperature to 180oC.
In an electric mixer with a paddle attachment, mix together sugar, flour, polenta, baking soda and salt.
Turn the mixer to low speed. Add eggs and melted butter. Keep mixing until all the ingredients are well combined. Add orange and lemon zest and pistachios. Mix for 30 seconds or so, still at low speed.
Form dough into two equal logs and place on an oven tray lined with baking paper. Bake for around 20 minutes until logs are firm.
Remove, cool for 10 minutes. Meanwhile, reduce oven temperature to 90oC. Using a bread knife, cut ½ cm thick biscotti slices from each log. Place slices on the baking paper. Place in the oven until dry, about 70-90 minutes.