Instructions

1. In a large mixing bowl, beat butter and sugar with an electric beater until light and fluffy. Add egg and mix until combined. In a separate jug, add buttermilk and vanilla and stir.
2. Add flour, cocoa powder and baking soda, along with the buttermilk, and  beat briefly to combine. Add food gel and mix until the mixture is evenly coloured. Cover with plastic wrap and pop in the fridge for one hour.
3. Preheat oven to 180 C (350 F) standard / 160 C (320 F) fan-forced. Line two baking trays with baking paper.
4. Use a large cookie scoop to measure out tablespoons of the mixture and place on prepared trays.
5. Bake whoopie pies in the oven for 10 minutes or until they spring back when gently touched. Move to a wire rack to cool completely.
6. To make the cream cheese frosting, add butter and cream cheese to a large mixing bowl. Beat with an electric mixer for 2-3 minutes until smooth and creamy. Add vanilla. Add sugar, 1 cup at a time, and continue to beat until smooth.
7. Once the whoopie pies are completely cooled, spread the icing onto one pie and then gently add the other on top and squish gently to push the icing to the edges. Continue with the remaining pies until you have 12 whoopie pies.