Simon Rimmer makes avocado cake with polenta on Sunday Brunch.

The ingredients are: 125g butter, 350g sugar, 150g ripe avocados, 2 eggs, 1 tsp vanilla, 175ml buttermilk, 375g flour, 65g polenta, Pinch of salt, 4g baking powder and 4g bicarbonate of soda.

For the topping: 25g butter, 350g icing sugar, 1 tsp ground ginger and Zest 1 lime.

To prepare the cake, preheat the oven to 180°C/gas mark 4. In a bowl, beat the butter, sugar and avocado with an electric whisk for a full 5 minutes.

Mix in the eggs, vanilla and buttermilk, then then fold in all the dry ingredients.

Spoon into a greased and lined loaf tin and bake for 45 minutes.

Allow the cake too cool completely once cooked.

For the topping, whisk the butter, icing sygar and ginger together with an electric whisk, then spread on the cake. Grate on the lime to finish.