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Ingredients
150gsoftened unsalted butter
150gcaster sugar
100glight soft brown sugar
1large egg
250gplain flour
1teaspoonbaking powder
½teaspoonsalt
45gcocoa powder
150gdark chocolate chips
Instructions
In a large bowl, cream the butter and both sugars together with an electric whisk until smooth and fluffy. Add the egg and mix well.
150 g softened unsalted butter, 150 g caster sugar, 100 g light soft brown sugar, 1 large egg
In a separate bowl, mix the flour with the baking powder, salt and cocoa powder. Add to the butter mixture and mix well to form a stiff dough. At first, it will look like there is too much flour, but whisk slowly and it will form a stiff dough. Add the chocolate chips.
250 g plain flour, 1 teaspoon baking powder, ½ teaspoon salt, 45 g cocoa powder, 150 g dark chocolate chips
Tip the dough onto a large piece of clingfilm or greaseproof paper. Roll the dough into a cylinder shape 27cm long and 6cm wide. Place in the fridge to firm up for at least 2 hours.
Line two baking trays with parchment paper. Preheat your oven to 160°C/Gas 3.
Unwrap the dough, cut into 16 equal slices and place on the prepared trays, leaving room to spread. Bake for 12 to 15 minutes. The cookies should have risen and spread out. They will still be soft when you remove them from the oven, so leave to firm on the tray for a few minutes before cooling completely on a wire rack.