If slicing your Creme Eggs, place them in the freezer for 30 minutes to make cutting easier and prevent the filling from oozing out.
I use a stand mixer with the paddle attachment, mix the butter and caster sugar together until combined. This will take 1-2 minutes in an electric mixer (I use speed 3).
Add the dry ingredients (Baking Powder, Salt, Bicarb, Plain Flour, Cornflour and Chocolate) into the bowl and mix for 30 seconds.
Add in your egg, egg yolk and golden syrup into the mixture and mix until a cookie dough is formed (the dough will start coming away from the bowl which means it is ready!)
Divide the dough into cookie balls, I weighed the dough out to make each cookie 110g-120g each!
Flatten each piece slightly and place half a Creme Egg in the centre.
Wrap the dough around the Creme Egg, sealing it well so the filling is fully enclosed.
Place them on a lined baking tray, or into a container lined with baking paper. Chill them in the freezer for 1 hour.
While your dough is chilling, pre-heat your oven to Gas Mark 5/190c/170 Fan.
Bake for 12-14 minutes, remove from the oven and immediately press the remaining half Creme Egg onto the top of each cookie.
If your cookies have spread slightly, use a round cookie cutter to gently swirl them back into shape while they are still hot.
Allow the cookies to cool on the tray for 10 minutes before transferring to a wire rack to cool completely.