Preheat oven to 325 degrees F. Line an 8-inch metal pan with parchment paper.
If your powdered sugar, cocoa powder and flour are lumpy, sift them.
In a mixing bowl, whisk together the sugar, powdered sugar, flour, cocoa powder and salt, then stir in the chocolate chips.
In another bowl, whisk together the eggs, oil, vanilla and water.
Add dry mixture to wet mixture and beat with a heavy duty scraper until shiny.
Scrape the very thick batter into pan and bake for 40 to 48 minutes at 325. The long baking time goes with the lower temp, so if your oven runs hot either lower the temp or check the brownies earlier.
Let cool for about 10 minutes, then grasp foil, lift from pan and let cool completely.