Rose-water-and-pistachio biscuits with buffalo mozzarella, nectarines and basil

Cover the pistachio nuts with lukewarm water and soak them for 1 hour. This will help you to slice through the pistachios when cutting the dough. Strain the water.
Cream the butter and caster sugar until white and fluff y. Add the egg and rosewater, mix well until smooth and fold in the nuts.
Gently fold the flour into the mixture and use your hands to combine the stiff dough while kneading it for 30 seconds. Divide the dough in two.
Dust a large piece of plastic wrap with a little flour. Roll each piece of dough into a log, roughly 6cm in diameter.
Cover with clean plastic and place in the refrigerator for 30 minutes. Preheat the oven to 180°C.
Remove and cut the dough into 5mm slices. Place the biscuits 2cm apart on a baking tray lined with baking paper.
Bake in the oven until golden brown, about 10 to 15 minutes. Cool on a wire rack.
Top the biscuits with sliced mozzarella, sliced nectarines and fresh basil. Serve with freshly cracked black pepper.