Amiable Cookies with Mean Choc Chips

Cromagnon made these by accident when he used a bar of intense fuck-off 85% cocoa solids cooking chocolate instead of the normal stuff meant for eating. It was an adaptive mutation and we've been making them this way ever since. The cookie dough should be as mild and all-American as possible to contrast with the dark, bitter chocolate.
They're freezer cookies, so you make a vast batch of dough, freeze it in a cylinder shape, and slice off a few cookies at a time for baking. I defy the Breakfast Police and eat them for weekday breakfasts with orange juice and an espresso. Oh yes.
Makes about 100 cookies but not necessarily all at once.

Recipe
To make the dough, beat 175g caster sugar and 110g brown soft sugar with 225g butter (at room temperature), then beat in 2 eggs and 1 tsp vanilla extract.
Next, sift 450g plain flour with 1/2 tsp salt, 1 tsp baking powder and 1/2 tsp bicarbonate of soda, and mix all that in. Finally stir 55ml milk and 100g very dark chocolate chunks through the dough. (Green & Black, Lindt and Cote d'Or all make 100g bars with 85-90% cocoa solids which you can chop up into little bits). Chill the mixture for an hour or so in the fridge if you have time.
Then tip it out onto a floured board and squish it into two sausage shapes about 5cm across and 30cm long. Wrap them in baking parchment and shove them in the freezer until needed. They keep for a good few weeks.

When you want cookies, preheat the oven to 200 deg C. Cut off 5mm slices of dough like slicing a salami, and put them on a baking sheet lined with baking parchment (or just well greased). Leave room between them so they can spread out a bit. Bake them for 7 minutes. Let them cool slightly before trying to remove them from the tray, as they're still very soft when they leave the oven.