Mix the baking powder to the plain flour and sift and keep it aside.
In a mixing bowl, mix together butter and sugar till the sugar almost dissolves.
Add in the egg and beat till its combined, if it starts to curdle do not panic. It's the temperature of the butter which makes it like that. Chill the batter in the fridge for some time and continue before continuing the next step.
Add the flour mix and slowly combine everything together. Do not over mix.
Add in the chocolate chips and mix it in.
Spoon the mix to a baking tray and bake it @ 160 C / 320 F for ~ 18 to 20 mts.
Around 15 mts open the oven door and turn the tray to get even cooking.
Recipe by Seemology at https://www.seemology.com/cake-cookies/