Skye Gyngell's panforte with candied pumpkin and pistachios

Name: Skye Gyngell's panforte recipe
Prep time: 20 mins
Cook time: 50 mins
Yield: Serves 6
Ingredients: 450g almonds; 450g shelled pistachios; 240g candied orange peel; 240g candied pumpkin (or mixed candied peel); 185g plain flour; 1tsp ground cinnamon; 1/4tsp ground cloves; 1/2tsp ground nutmeg; 340g honey; 300g sugar; 150g corn syrup; Butter, for greasing; Sheet of rice paper, large enough to cover a baking tray; Icing sugar, for dusting