Put the sugars and the softened butter into the largest mixing bowl you have
Cream together, either with a wooden spoon or (preferably) with an electric whisk till you have a smooth mixture that has lightened a little in colour.
Add the egg and mix well with the electric whisk
Sift the flour, baking powder and salt into the mixture
Using a spatula or metal spoon, fold the mixture together till you have a cohesive dough
Stir through the chocolate chips and chopped ginger
Cut out two large pieces of cling film
Divide the dough roughly in half and put a piece of dough on each sheet of cling film
Spread them out into a rough log shape with your hands or with a spoon
Use the clingfilm to roll up into sausages, making sure there's an inch or so of film at each end of each sausage to seal up the rolls
Put the sausages in the fridge and chill until firm - around an hour minimum
Set the oven to 175c and line a baking tray with baking parchment or silicon film
Take one sausage out and slice off around 1/2cm (1/4 inch) rounds. You only need to cut the number of cookies you want to bake. You can store any remaining dough in the fridge in clingfilm or freeze it
Bake the cookies in the oven for 10-15 minutes till they are a golden brown at the edge.
Take the tray out of the oven and allow the cookies to cool for 10 minutes before transferring to a wire rack
Eat while warm or allow to cool completely before storing in an airtight tin