Preheat oven to preheated 350°F/180°C/160°C fan/gas 4 and line a 12-hole cupcake tin with paper cupcake cases.
Cream together the Kerrygold butter and sugars until light and fluffy.
Add the eggs, one at a time, along with a spoonful of flour, beating well.
Sift over the dry ingredients.
Add the vanilla and the buttermilk and mix well.
Fold in the grated, drained courgettes.
Spoon into the prepared cupcake cases.
Bake in the centre of the oven for 20-25 minutes until golden brown and springy to the touch.
Cool completely on a wire rack.
To make the cream cheese frosting
Beat the Kerrygold butter until smooth and creamy.
Add the cream cheese and vanilla bean paste and mix well.
Sift over the the icing sugar.
Mix gently until combined. Do not overmix.
Frost the cupcakes using a large star shaped nozzle and decorate with chopped nuts, if desired.
How to make thick, pipeable cream cheese frosting
The cream cheese frosting recipe quantities listed in this recipe make a thinner cream cheese frosting, the kind you would find on the top of a carrot cake. If you want to make a thicker, pipeable frosting, reduce the butter and cream cheese quantities by half but use the full amount of icing sugar. You may need to add a little extra icing sugar to get the desired consistency, depending on the time of year/humidity. Just keep adding the icing sugar. It'll work eventually!
Tips for baking with courgettes
Courgettes can be quite watery when baking, so the trick is to drain the excess water from the grated vegetable before adding them to your bake.Grate the vegetable onto a clean dish towel or paper towel, top with another one and leave to drain while you prepare your cake batter.