In a large bowl, stir the cocoa and baking soda together. Stir in 1/3 cup butter, add the boiling water, and stir till the mixture thickens. Add the sugar, eggs, and remaining 1/3 cup of butter. Stir till smooth. Add the flour, vanilla, and salt and blend well. Stir in the chips and pour the mixture into the greased pan.
Bake for 35-40 minutes or until the brownies begin to pull away from the sides of the pan.
Allow the brownies to cool completely in the pan or on a wire rack. Eat them up, Yummy.