Let's start with the cookie dough, add all ingredients to a free-standing mixture and beat until well combined, forming a sticky yet firm dough.
Flatten of a piece of cling film (about 1.5-2cm thick), wrap it up and place in the freezer until semi solid but still able to cut through.
For the cupcakes, sift together all the dry ingredients (except the chocolate chips) in to a free-stand mixer.
Add the eggs and butter and beat for 1 minute.
Lower the speed and add the milk, vanilla and chocolate chips before turning mixer back up for 1 more minute, not forgetting to scrape down the sides during.
Fill paper cases about two-thirds full.
Bake between 16-20 minutes or until cake springs back when touched.
Leave cupcakes out to cool while we move onto the buttercream.
Beat butter in free-standing mixer for 5 minutes, scraping sides down occasionally.
Sift icing sugar and add to the butter in two stages, beating for another 3 minutes between additions.
On a slow speed add the milk then turn mixer speed back up for another 5 minutes.
Once the cupcakes are cool pipe a big blob of buttercream on the top.
Finally take the cookie dough out from the freeze and chop it up into chucks (big/small, you decide) and plonk a piece of the cookie dough right into the top of the buttercream. Sweetness overload!
Recipe by Baker Gatherer at https://bakergatherer.com/cookie-dough-cupcake/