In a medium pot over medium–low heat, combine all dry ingredients. Add chocolate chunks and soy milk. Whisk for about 30 minutes or until very smooth and thickened.

Remove from heat. Add the margarine and whisk until melted and fully incorporated. Pour into a bowl and cover with plastic wrap (touch plastic wrap to the surface of the pudding to prevent the pudding from developing a skin). Allow to cool completely.

Preheat oven to 400 degrees. In a large bowl, whisk the margarine and brown sugar together. Whisk for five minutes or until lightened and smooth. Add in vanilla and egg, and mix to fully incorporate. Add in flour, salt, and baking powder and mix with a fork until fully incorporated. Add in chocolate chips.

Press the cookie dough into a round Pyrex or oven-to-table dish and bake for 20 minutes. Top with cold pudding and serve immediately.