Preheat the oven to 170C (325F)

Put the room temperature butter and sugar into your mixer and beat on medium speed until light and fluffy

Add the egg and beat on a higher speed until all is well combined

In a small dish mix together the matcha powder with vanilla extract and your food colouring until you have a thick paste

Add the green paste mixture to the mixing bowl with the butter and sugar and continue mixing until you have a lovely green cake batter

Scrape down any excess mixture from the sides with a spatula then turn the mixer down to slow and slowly pour in half the buttermilk

Beat until well mixed, then add half the flour

Repeat this process until you've no more flour or buttermilk.

Scrape down the sides of the bowl and turn the mixer to a high speed and mix until you have a very smooth even mixture

Once you have a lovely smooth mixture, turn the mixer to low and add the salt, bicarbonate of soda and the vinegar

Beat until all well combined, turn up the speed and continue beating for a few minutes

Scoop the mixture into cupcake cases until 2/3rd full and bake in the preheated oven for 20-25 minutes, or until the sponge springs back when pressed, or a skewer inserted into the centre comes out clean

Leave the cupcakes to cool in the tin for 5 minutes before transferring to a wire rack to cool fully.

Once the cupcakes are cooled you can spoon on the cream cheese frosting.

Beat the icing sugar and butter together in a free standing mixer, with paddle attachment, on medium speed (you can also use electric whisk or do this by hand but will take longer)

Once the butter and icing sugar mixture is well combined add the cream cheese and the matcha powder in one go and beat until it's all incorporated

Turn the mixer to a medium-high speed and continue beating for at least 5 minutes or until it is light and fluffy.