Preheat oven to 180C/350F.
Lightly butter a 20 cm/8 inch springform pan.
Separate the egg and place the egg white in a large bowl, and put the egg yolk aside for the end of the preparation. Gently whisk the egg white, and then add the almonds, pistachios, icing sugar, flour, zests, and rosewater.
Mix to a paste.
Divide the mixture into 8 equal portions (around 50g each).
Roll each into a sausage shape about 20 cm in length.
Remove one sheet of filo pastry from your pile (keeping the remaining pastry covered with a clean tea towel), and place the sheet with the long side towards you.
Gently brush butter over the pastry and place another sheet on top, also brushing the top with butter.
Place two of your almond ‘sausages’ side by side at the front of the pastry leaving a gap of around 2 to 3 centimetres around the edges (sides and front).
Roll up to enclose the filling. Form into a coil and sit the coil, seam side down, in the centre of the tin, tucking under the unfilled ends of the pastry to enclose the filling.
Continue in this manner to make three more pastry ‘snakes’ shaping each around the smaller coil to make a large coil.
If the coil breaks, cut small pieces of some extra filo, brush with a little egg yolk and press the filo onto the breaks.
Add the cinnamon to the remaining egg yolk and brush over the coil.
Bake for 25-30 minutes or until golden brown. Dust with icing sugar.
Serve with cream, ice-cream or a date sauce!