Mix the butter with sugar for 5 minutes or until fluffy and creamy.

Stir in the eggs, one by one, mixing well after each egg addition. Stir in the vanilla and orange zest as well.

Combine the flour with polenta, baking powder and salt in a bowl. Mix half of the flour into the batter.

Add the orange juice and fold in the remaining half of the flour mixture.

Pour the batter into your prepared pan and bake in the oven for 40 minutes or until golden brown and a toothpick inserted in the cake comes out clean.

When done, remove from the oven and let the cake cool in the pan for 10 minutes. Turn the cake upside down on a platter and let it cool completely.

Combine the powdered sugar with blood orange juice and mix well.

The glaze should be thick but still slightly runny. If it's too thin, add more sugar until it reaches the desired consistency. If it's too thick, add a few drops of orange juice at a time until it thins down to the consistency you're after.

Pour the glaze over the chilled cake and let it set.

Decorate with blood orange slices if you wish.