Bake the cookie dough base

• Press the cookie dough evenly into a pie dish.
• Bake at 180 °C until baked through and lightly golden.

Cool the base

• Let the baked cookie base cool completely in the dish.

Make the chocolate frosting

• Beat the butter and cocoa powder together.
• Fold in the powdered sugar and vanilla.
• Add the milk and beat until smooth and fluffy.

Decorate and serve

• Pipe the frosting around the edge of the cooled pie.
• Decorate with sprinkles if desired, then slice and enjoy.