Add the unsalted butter or baking spread to a bowl, and add the two sugars. Beat together until creamy (I use my stand mixer).
Add in the egg, vanilla extract and peppermint extract.
Add in the plain flour, cocoa powder, baking powder, bicarbonate of soda, and salt and beat together until a cookie dough is formed!
Add in the chocolate chips and Mint Aero bubbles and beat until distributed well!
Weigh the cookies out into eight cookie dough balls - they're about 115-120g each!
Once they are rolled into balls, put the cookie dough in the freezer for at least 30 minutes, or in the fridge for an hour or so to chill.
Whilst the cookie dough is chilling, preheat your oven to 180C Fan, or 200C regular! If your oven runs hot, go for 160C-170c.
Take the cookies out of the freezer/fridge and put onto a lined baking tray. I put four cookies per tray!
Bake the cookies in the oven for 11-12 minutes. I don't personally flatten the cookies, as they flatten enough during baking - however, if you like flat cookies, flatten them a bit before baking.
Once baked, leave them to cool on the tray for at least 30 minutes, as they will continue to bake whilst cooling - trust in this step!
Once cooled, ENJOY!
Notes
These are best eaten on the day of baking, but can be revived by microwaving for 15-30 seconds, or putting into a hot oven for 2-3 minutes!
You can freeze the raw cookie dough easily, and bake from frozen if you don't want to bake the entire batch!
If you are baking straight from frozen after some time, I usually bake for 12-14 minutes!
If you prefer your cookies flatter, you can squish them down slightly before baking but I don't do this personally!
If you can't access one of the sugars, use all of the other one - i.e. all granulated, or all light brown sugar. Using other sugars can change the texture.
You can make them smaller by splitting the mixture into 12, and bake for 9-10 minutes!