Prepare the brownie mixes according to the instructions on the box.
When they are done, let them cool and remove them from the pans.
Level the brownie cakes.
Stack the brownie layers.
Top with powdered sugar.
Notes
***Nutrition will vary widely based on which brownie mix you use, as well as the ingredients needed to make them.The serving sizes can vary and you will get at least 24 servings from stacking the brownies the way I did in the photos. If you cut them smaller you can get even more servings. If you've never leveled a cake before check out this tutorial from Serious Eats.If you don't want to worry about leveling, you could make a brownie tower instead by cutting a pan of brownies into individual sizes and then carefully stacking them in a circular tower on top of each other.