Take a box of these:
and, then a box of these:
Make both boxes, in the same bowl, according to the package direction. Spread the ooey gooey goodness, known as brownie batter, into a lightly greast 9 by 13 inch pan. Bake in a 325 degree oven, for about 45 - 50 minutes, depending on the quirks of your oven. Cool completely, and then enjoy.
You will get this:
and eventually this, in LESS THAN 24 hours: