Preheat the oven to 325 degrees F. Grease an 8 inch square Pyrex dish and line with a strip of parchment so that the brownies can be removed from the pan.

In a medium saucepan, gently melt the butter. Add the water and both sugars and bring to a boil. Remove from heat and stir in chopped chocolate and chocolate chips until melted and smooth. Chocolate will begin to thicken as you stir.

Whisk the cold eggs in a second bowl, and then whisk or stir them into the chocolate mixture. Whisk in the vanilla. Combine the flour, baking soda and salt; stir into the chocolate mixture. Add the remaining chocolate chips (make sure that the batter is not so hot that it melts them) and spread batter evenly into the prepared pan.

Bake for 25 minutes on the center rack until brownies appear set. Let cool to room temperature and then chill slightly. Lift from pan and cut into squares.