Try serving this lovely orange cake with a citrusy sparkling cocktail. The Alberti brothers suggest serving the cake with non-dairy ice cream, but it would also be delicious with regular ice cream.
Preheat the oven to 350ºF (180°C) and grease a 9-inch round lined springform loose-bottomed cake tin.
Place the eggs and sugar in a large bowl and whisk until the sugar has dissolved and the eggs are pale in color.
Fold the orange zest and juice into the mixture. Then in a separate bowl mix the polenta, ground almonds and baking powder together and add to the bowl and mix well until all combined.
Pour the mixture into the tin and spread evenly and bake for 35-40 minutes. Cool in the tin and set aside.
To prepare the syrup, pour the sugar and orange juice into a saucepan and heat slowly until the sugar dissolves. Simmer for around 10 minutes or until the liquid has reduced by half and the sauce thickens slightly.
Remove the cooled cake from the tin and place on a serving plate.
Slice the cake up and serve each slice with a scoop of dairy-free vanilla ice cream. Drizzle the cake and ice cream with the syrup. Scatter crumbled Amaretti biscuits on the plate and over the ice cream.