Add your unsalted butter and dark brown soft sugar to a bowl and beat together until creamy. Add in your egg, and beat again. If using vanilla, add it in now! Add in the plain flour, ground ginger, ground cinnamon, ground nutmeg, baking powder, bicarbonate of soda, and salt and beat until a cookie dough is formed! Add in the chocolate chips and beat again until they're distributed well!
Weigh your cookies out into eight cookie dough balls - they're about 120g each! Once they're rolled into balls, put your cookie dough in the freezer for at least 30 minutes, or in the fridge for an hour or so! 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 your 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 12-14 minutes.
Once baked, leave them to cool on the tray for at least 30 minutes, as they will continue to bake whilst cooling! ENJOY!