How to make a gorgeous cookie cake!
Beat together the butter and sugar until well creamed, then follow up with the eggs and egg yolks and vanilla extract, mix well until fully merged and consistent in colour. Sift in the dry ingredients and fold through until well combined. Stir through the chocolate chips and sprinkles.
Push this mixture into a lightly greased springform tin (9cm / 23cm) ensuring it is even then bake in a pre-heated oven at gas 4 (or equivalent see oven temperature conversion chart) for 25minutes leaving on a wire rack to cool down fully.
Meanwhile make the buttercream by beating together the butter with the icing sugar, then adding the cream and vanilla extract, add icing sugar if needed to thicken then put into a piping bag with a star nozzle.
With the cookie fully cooled, pipe on a circle of buttercream around the edge of the cookie and finish with sprinkles onto the icing and the cookie centre. Enjoy this super easy cookie cake!