Lemon Ricotta Cake
          INGREDIENTS
          
            - 180g (¾ cup) butter, softened
 
            - ½ to ¾ cup caster sugar
 
            - (optional) ¼ cup polenta if less sugar is preferred
 
            - zest from 3 lemons
 
            - 1 teaspoon lemon extract (or 2 teaspoons lemon juice)
 
            - 3 eggs, separated
 
            - 250g (1 cup) ricotta, strained
 
            - ½ cup plus 2 tablespoons all-purpose flour
 
            - 2 teaspoons baking powder
 
            - pinch of salt
 
          
          METHOD
          
            - Preheat oven to 160°C.
 
            - Lightly grease and flour a 20cm spring-form pan.
 
            - Beat the butter and sugar (plus polenta top-up) with a hand mixer until light and fluffy.
 
            - Add the lemon zest, extract, egg yolks and ricotta cheese and beat until smooth.
 
            - Mix together the flour, baking powder and salt, and beat into the butter mixture just until combined.
 
            - Wash your beaters well, and then beat the egg whites in a separate bowl until stiff.
 
            - Gently fold the egg whites into the batter then spoon the batter into your prepared tin.
 
            - Bake for about 45 minutes, or until a skewer comes out clean.
 
            - Allow to cool to room temperature before serving.
 
          
          (based on Lemon Ricotta Cake at Italian Food Forever)