In an electric mixer, cream the butter and sugar together.
Then add the soy milk and vanilla and mix in.
Add your flour, baking soda, baking powder, cornstarch and salt to a mixing bowl and mix together.
Add the dry ingredients to the wet and mix in by hand (don't use your electric mixer for this part) until properly mixed into a thick cookie dough.
Add the chocolate chips and mix in to distribute as evenly as possible.
Preheat the oven to 350°F (180°C).
Roll into balls and place evenly on a baking tray covered with parchment paper. Aim for 20 cookies.
Place into the oven and bake for 10-12 minutes until the edges are set and they are very slightly browned on top.
When they come out of the oven, press a few more chocolate chips into the tops of the warm cookies.
Allow to cool and firm up directly on the tray.
Once properly cooled store in an airtight container.